Sunday, December 6, 2009

Review Questions

Integrate the following DO NOT FORGET THE +c
1. dy/dx = 5x^3 + 2x^2 + 5
2. dy/dx = 6x + 1
3. dy/dx = 2
4. dy/dx = 8x^5 - 5x^3 + 4x
5. dy/dx = 7x^2 + 3x + 4

6. A particle moves in a straight line and at point P, it's velocity is given as v = 7t^2 - 5t +3. The particle comes to rest at point Q.1. What is the acceleration at Q if it arrives at Q when t=7?2. How far does the particle travel in t=1 to t=4?

7. Find dy/dx of the following:

1. y = 6x^3 + 4x^2 - 5x
2. y = x^-3 + 16
3. y = 4x + 4
4. y = 3x^4 + 3(x^2 + 5)
5. y + 6 = 4x + 9y - 3x^2


8. A curve has equation y = 4/(2)^.5, find dy/dx
9. A curve is such that dy/dx = 16/x^3 and (1,4) is a point on the curve, find the equation of the curve.
10. y = 6theta - 2sin theta, find dy/dx
11. The equation of a curve is y = 2x + 8/x^2, find dy/dx and d^2ydx^2
12. A curve is such that dy/dx = 2x^2 -5. Given that the point (3,8) lies on the curve, find the equation of the curve.

212 comments:

  1. 1. dy/dx = 5x^3 + 2x^2 + 5
    d^2y/dx^2=15x^2+4x

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  2. 2. dy/dx = 6x + 1
    d^2y/dx^2=6

    3. dy/dx = 2
    d^2y/dx^2=0

    4. dy/dx = 8x^5 - 5x^3 + 4x
    d^2y/dx^2=40x^4-15x^2+4

    5. dy/dx = 7x^2 + 3x + 4
    d^2y/dx^2=14x+3

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  3. 7. Find dy/dx of the following:

    1. y = 6x^3 + 4x^2 - 5x
    dy/dx=18x^2+8x-5

    2. y = x^-3 + 16
    dy/dx=-3x^-4

    3. y = 4x + 4
    dy/dx=4

    4. y = 3x^4 + 3(x^2 + 5)
    dy/dx=12x^3+6x

    5. y + 6 = 4x + 9y - 3x^2
    dy/dx=4+9-6x
    dy/dx=13-6x

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  4. 11. The equation of a curve is y = 2x + 8/x^2, find dy/dx and d^2ydx^2
    y= 2x+8x^-2
    dy/dx= 2-16x
    d^2y/dx^2=-16

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  5. This comment has been removed by the author.

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  6. 4.

    dy/dx = 8x^5 - 5x^3 + 4x

    y=(8x^6/6)-(5x^4/4)+(4x^2/2)+c

    y=(4x^6/3)-(5x^4/4)+(2x^2)+c

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  7. Alright....i'm not sure if i'm doing this correct anymore..... What is the integral of a constant????

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  8. Is the integral of a consatnt 'c'......?? Sombody please clarify this.....

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  9. 4. dy/dx = 8x^5 - 5x^3 + 4x
    S = 8x^6/6 - 5x^4/4 + 4x^2/2 + c

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  10. 1.

    dy/dx = 5x^3 + 2x^2 + 5

    y=(5x^4)+(2x^3/3)+(5x)+c

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  11. 5. dy/dx = 7x^2 + 3x + 4
    S = 7x^3/3 + 3x^2/2 +c

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  12. This comment has been removed by the author.

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  13. Ques. 7
    1. y = 6x^3 + 4x^2 - 5x
    dy/dx = 18x^2 + 8x - 5

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  14. 5.

    dy/dx = 7x^2 + 3x + 4

    y=(7x^3/3)+(3x^2/2)+(4x)+c

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  15. Ques 7
    2. y = x^-3 + 16
    dy/dx = -3x^-4 + 0

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  16. 7

    1.

    y = 6x^3 + 4x^2 - 5x

    dy/dx =(18x^2)+(8x)-5

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  17. 7.
    2.
    y = x^-3 + 16

    dy/dx = (-3x^-4)

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  18. Ques. 7
    5. y + 6 = 4x + 9y - 3x^2
    9y -y = 3x^2 - 4x + 6
    8y = 3x^2 - 4x + 6
    y = (3x^2 - 4x + 6) / 8
    y = 3x^2 - 4x + 6 + 8^-1
    dy/dx = 6x - 4 + 0 + 0
    dy/dx = 6x - 4

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  19. 7.
    4.
    y = 3x^4 + 3(x^2 + 5)

    y=(3x^4)+(3x^2)+(15)

    dy/dx =(12x^3)+(6x)

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  20. Alright... 7 part 5 was very tricky....
    Could someone tell me if what i did is correct. especiall the part where i carried across the 8 and brought it up to the power of -1???????

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  21. 7.
    5.
    y + 6 = 4x + 9y - 3x^2

    y=[(3/8)x^2]-[(4/8)x]+[6/8]

    dy/dx =[(3/4)x]-[1/2]

    you made a mistake with no.5

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  22. you were supposed to multiply the 8^(-1) by everything in the brackets

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  23. for ex

    (8+y)/x

    =[x^(-1)]*(8+y)

    = [8x^(-1)] + [yx^(-1)]

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  24. #7:
    (1) y= 6x³ + 4x²- 5x
    dy/dx = 18x² + 8x -5
    (2) y= x-3 +16
    dy/dx= -3x-4
    (3) y= 4x +4
    dy/dx= 4
    (4) y=3x4 + 3(x²+5)
    y= 3x4 +3x² + 15
    dy/dx= 12x³ + 6x
    (5) y + 6 = 4x +9y – 3x²
    6+3x²-4x= 9y – y
    6 + 3x² - 4x = 8y
    (6 + 3x² - 4x) + 8-1 = y
    6x – 4 = dy/dx

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  25. #12:
    dy/dx = 2x² - 5
    in order to obtain the curve, the gradient must be integrated:
    y = ∫ (dy/dx) dx
    y = ∫ 2x² - 5 + c
    y = (2/3) x³ - 5x + c
    substitute point ( 3,8) to find c:
    8 = (2/3) 3³ - 5 (3) + c
    8 = -9 +c
    17 = c
    Therefore equation of the curve:
    y = (2/3) x³ - 5x + 17

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  26. #1:
    dy/dx = 5x³ + 2x² +5
    y = (5/4) x4 + (2/3) x³ + 5x + c

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  27. This comment has been removed by the author.

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  28. dy/dx = 5x^3 + 2x^2 + 5
    then
    d^2y/dx^2=15x^2+4x

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  29. #4:
    dy/dx = 8x5 – 5x³ + 4x
    y = (8/6) x6 – (5/4)x4 + 2x² + c

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  30. #5:
    dy/dx = 7x² + 3x + 4
    y = (7/3) x³ + (3/2) x² + 4x + c

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  31. 4. dy/dx = 8x^5 - 5x^3 + 4x
    =(8/6)x^6-(5/4)x^4- 2x^2

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  32. 5. dy/dx = 7x^2 + 3x + 4
    y=(7/3)x^3+(3/2)x^2 + 4x

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  33. v = 7t^2 - 5t +3.
    dv/dt=14t-5
    when t=7
    subs into equ.
    14(7)-5= 93
    so acc. is 93
    intergrate v
    (7/3)t^3-(5/2)t^2 +3t
    when t=1
    subs into v
    (7/3)(1)^3-(5/2)t^2+3(1)
    =(7/3)-(5/2)+3
    =2/5/6

    when t=4
    subs into v
    (7/3)(4)^3-(5/2)(4)^2+3(4)
    okk i doh no if i doing this correct

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  34. 1. y = 6x^3 + 4x^2 - 5x
    dy/dx=18x^2+8x-5

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  35. 4. y = 3x^4 + 3(x^2 + 5)
    dy/dx=12x^3+6x

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  36. 5. y + 6 = 4x + 9y - 3x^2
    dy/dx=4+9-6x
    dy/dx=13-6x

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  37. This comment has been removed by the author.

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  38. number (2)
    dy/dx = 6x + 1
    y= 3x^2+x+c

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  39. number (4)

    dy/dx = 8x^5 - 5x^3 + 4x
    S = 8x^6/6 - 5x^4/4 + 4x^2/2 + c

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  40. number (5)

    dy/dx = 7x^2 + 3x + 4

    y=(7x^3/3)+(3x^2/2)+(4x)+c

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  41. number (7)
    part 1

    y = 6x^3 + 4x^2 - 5x

    dy/dx =(18x^2)+(8x)-5

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  42. number (7)
    part 2

    y = x^-3 + 16
    dy/dx = (-3x^-4)

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  43. number (7)
    part 3

    y = 4x + 4
    dy/dx = 4

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  44. number (7)
    part 4

    y = 3x^4 + 3(x^2 + 5)
    y=(3x^4)+(3x^2)+(15)
    dy/dx =(12x^3)+(6x)

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  45. number (7)
    part 5

    y + 6 = 4x + 9y - 3x^2
    y=[(3/8)x^2]-[(4/8)x]+[6/8]
    dy/dx =[(3/4)x]-[1/2]

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  46. number (11)

    eq'n of curve is y = 2x + 8/x^2, find dy/dx and d^2ydx^2
    y= 2x+8x^-2
    dy/dx= 2-16x
    d^2y/dx^2=-16

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  47. number (12)

    dy/dx = 2x² - 5
    to get a curve, the gradient must be integrated:
    y = ∫ (dy/dx) dx
    y = ∫ 2x² - 5 + c
    y = (2/3) x³ - 5x + c
    substitute point ( 3,8) to find c:
    8 = (2/3) 3³ - 5 (3) + c
    8 = -9 +c
    17 = c
    Therefore equation of the curve:
    y = (2/3) x³ - 5x + 17

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  48. number (6)

    v = 7t^2 - 5t +3
    dv/dt=14t-5
    when t=7
    subs into equ.
    14(7)-5= 93
    so acc. is 93
    intergrate v
    (7/3)t^3-(5/2)t^2 +3t
    when t=1
    subs into v
    (7/3)(1)^3-(5/2)t^2+3(1)
    =(7/3)-(5/2)+3
    =2/5/6

    when t=4
    subs into v
    (7/3)(4)^3-(5/2)(4)^2+3(4)

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  49. #9:
    dy/dx = 16/x³
    in order to obtain the curve, the gradient must be integrated:
    y = ∫ (dy/dx) dx
    y = ∫ 16/x³ + c
    y= ∫ 16x-³
    y = 8x-² + c OR y = 8/x² + c
    substitute point ( 1,4) to find c:
    4 = 8/1² + c
    4 = 8 +c
    -4 = c
    Therefore equation of the curve:
    y = 8/x² - 4

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  50. #1
    dy/dx = 5x^3 + 2x^2 + 5
    i.e y=5x^4/4 + 2x^3/3 +5x +c

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  51. number (1)

    dy/dx = 5x^3 + 2x^2 + 5
    d^2y/dx^2=15x^2+4x+c

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  52. miss i dont understand why u have to add +c

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  53. #4
    dy/dx = 8x^5 - 5x^3 + 4x
    y=8x^6/6 - 5x^4/4 + 4x +c

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  54. #5
    dy/dx = 7x^2 + 3x + 4
    y=7x^3/3 + 3x^2/2 + 4x +c

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  55. #6
    v = 7t^2 - 5t +3
    ueing loop
    dv/dt=14t - 5
    sud when t=7
    dv/dt=14(7)- 5
    dv/dt=98-5
    dv/dt=93

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  56. #6
    v = 7t^2 - 5t +3
    v=7t^3/3-5t^2/2+3x+c

    IS IT 3X +C OR 3t +C ???????????

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  57. sub when t=1
    v=7(1)^3/3-5(1)^2/2+3(1)+c
    v=7/3 -5/2 +3 +c

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  58. sub when t=4
    v=7(4)^3/3-5(4)^2/2+3(4)+c
    v=448/3 -80/2 +12 +c

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  59. This comment has been removed by the author.

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  60. 2. dy/dx = 6x + 1
    integrated
    y=3x^2+x+c

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  61. 1. dy/dx = 5x^3 + 2x^2 + 5
    integrated
    y=5x^4/4 + 2x^3/3 + 2x^3/3 + 5x + c

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  62. 4. dy/dx = 8x^5 - 5x^3 + 4x
    integrated
    y= 8x^6/6 - 5x^4/4 + 4x^2/2 + c

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  63. 5. dy/dx = 7x^2 + 3x + 4
    integrated
    y= 7x^3/3 + 3x^2/2 + 4x + c

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  64. No.7
    part 1

    1. y = 6x^3 + 4x^2 - 5x
    dy/dx= 18x^2 + 8x - 5

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  65. No.7
    4. y = 3x^4 + 3(x^2 + 5)
    y = 3x^4 + 3x^2 + 15
    dy/dx = 12x^3 + 6x

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  66. No.7
    5. y + 6 = 4x + 9y - 3x^2
    -8y = -3x^2 + 4x - 6
    y = -3x^2/-8 +4x/-8 -6/-8
    y = 3/8x^2 + 1/4x + 3/4
    dy/dx = 3/4x + 1/4

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  67. 8.
    y = 4/(2)^.5
    y = 4/32
    y = 1/8
    dy/dx = 0

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  68. 9.
    dy/dx = 16/x^3
    integrated
    y = 16x^-2/-2 + c
    y = -8x^-2 + c
    when(1,4)
    4 = -8(1)^-2 + c
    4 = -8 + c
    c = 12
    i.e. eq'n
    y = -8x^-2 + 12

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  69. 10. y = 6theta - 2sin theta
    dy/dx = 6 - 2 cos theta

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  70. 11.
    y = 2x + 8/x^2
    dy/dx = 2 + -16x^-3
    d2y/dx^2 = 48x^-4

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  71. 12.
    dy/dx = 2x^2 -5
    y = 2x^3/3 - 5x + c
    when (3,8)
    8 = 2(3)^3/3 - 5(3) + c
    8 = 18 - 15 + c
    c = 5
    i.e. eq'n
    y = 2x^3/3 - 5x + 5

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  72. Fadda Anonymous i saw that no one answered your question about the integral of a constant. *sigh*
    the integral of a constsnt is not c it is:
    (the constant)*(what you're integrating wrt)

    So if you're integrating 5 with respect to x, the answer is 5x + C, of course.

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  73. 1. dy/dx = 5x^3 + 2x^2 + 5
    integral of(5x^3 + 2x^2 + 5)
    =[(5x^(3+1)/4]+[2x^(2+1)/3]+ 5x + c
    =5x^4/4 + 2x^3/3 + 5x + c

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  74. 2. dy/dx = 6x + 1
    integral of (6x + 1)
    =[6x^(1+1)/2] + 1x
    =6x^2/2 + 1x
    =3x^2 + 1x

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  75. 4. dy/dx = 8x^5 - 5x^3 + 4x
    integral of (8x^5 - 5x^3 + 4x
    =[8x^(5+1)/6]-[5x^(3+1)/4]+[4x^(1+1)/2 + c
    =4x^6/3 - 5x^4/4 + 2x^2 + c

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  76. 5. dy/dx = 7x^2 + 3x + 4
    integral of (7x^2 + 3x + 4)
    =[7x^(2+1)/3] + 3x^(1+1)/2 + 4x + c
    = 7x^3/3 + 3x^2/2 + 4x + c

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  77. 7)
    #1
    y = 6x^3 + 4x^2 - 5x
    dy/dx=18x^2 + 8x - 5

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  78. #4
    y = 3x^4 + 3(x^2 +5)
    y=3x^4+3x^2+15
    dy/dx=12x^3+6x

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  79. #5
    y + 6 = 4x + 9y - 3x^2
    9y-y=-3x^2+4x-6
    8y=-3x^2+4x-6
    y=-3x^2/8+4x/8-6/8
    y=-3x^2/8+2x-6/8
    dy/dx=-6x/8+2

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  80. question #7
    part 1. y = 6x^3 + 4x^2 - 5x
    dy/dx = [(6*3)x^(3-1)] + [(4*2)x^(2-1) - 5
    dy/dx = 18x^2 + 8x - 5

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  81. #5
    y + 6 = 4x + 9y - 3x^2
    dy/dx=4+9-6x
    dy/dx=13-6x

    not sure which is correct

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  82. part 2. y = x^-3 + 16
    dy/dx = [(1*-3)x^(-3-1)
    dy/dx = -3x^-4

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  83. #9
    can someone tell me what to do from there

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  84. *iheartseanpaul* like u timeing me lol

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  85. 4. y = 3x^4 + 3(x^2 + 5)
    y = 3x^4 + 3x^2 + 15
    dy/dx = [(3*4)x^(4-1) + [(3*2)x^(2-1)
    dy/dx = 12x^3 + 6x

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  86. lol haha no snowhite lol i thought we were racing lol but i think u like way ahead of me lol but i'll catch up soon lol

    u ready for examz???? lol
    *sigh*

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  87. #10
    y = 6theta - 2sin theta
    dy/dx=6-2cos theta

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  88. lol ok yes i was racing lol

    no am not realy feelin prepared r u

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  89. #11
    y = 2x + 8/x^2
    y=2x+8x^-2
    dy/dx=2-16x^-3

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  90. #12
    dy/dx = 2x^2 -5
    y=2x^3/3-5x+c
    sub when x=3 & y=8
    8=2(3)^3/3-5(3)+c
    8=18-15+c
    8=3+c
    3+c=8
    c=8-3
    c=5

    y=2x^3/3-5x+5

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  91. This comment has been removed by the author.

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  92. 1.
    dy/dx = 5x^3 + 2x^2 + 5
    y = ∫5x^3 + 2x^2 + 5
    y = 5x^4/4 +2x^3/4 + 5x + c

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  93. 2.
    dy/dx = 6x + 1
    y = ∫6x + 1
    y = 3x^2 + x + c

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  94. 4.
    dy/dx = 8x^5 - 5x^3 + 4x
    y = ∫8x^5 - 5x^3 + 4x
    y = 4x^6/3 - 5x^4/4 + 2x^2 + c

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  95. 5.
    dy/dx = 7x^2 + 3x + 4
    y = ∫7x^2 + 3x + 4
    y = 7x^3/3 + 3x^2/2 + 4x + c

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  96. fadda annonymous, the integral of zero is 'c'. the integral of a constant is the same constant by 'x'. eg. the integral of 3 would be 3x...

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  97. the reason that the integral of zero is 'c' is that when you differentiate a constant you get zero and since integration is the opposite of differentiation, the integral of zero is 'c'.

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  98. hey, fadda anonymous, for question 7 part 5, you have to divide each term by 8...then differentiate. if all the terms were multiplied to each other then it would have been possible to state it like that but since all the terms are added, each term has to be evaluated separately...understand what i mean?

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  99. here's how to do #9 snowwhite

    since you already have the gradient ie.dy/dx=16/x^3 you can integrate this to find the equation of the curve so it will be:
    y =∫16/x^3
    y =∫16x^-3
    y =[16x^(-3+1)]/-2 + c
    y = -8x^-2 + c OR -8/x^2 + c
    now that you have the integral u can substitute the points (1,4) into the equation to solve for c..that will give:

    4 = -8/1^2 +c
    4 = -8/1 + c
    4 = -8 + c
    c = 4 + 8
    c = 12

    so the equation of the curve is y = -8/x^2 + 12

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  100. hey grapes, you did the differentiation part of question 6 correctly. but you did not have to integrate again as they already gave you the equation which is v = 7t^2 - 5t +3. all you have to do now is to use the limits that were given (t=4 and t=1) to find the area which, in this case, will be the distance travelled...

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  101. snowwhite,see above for explanation on the reason for 'c'.

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  102. also snow, see above for question six. however, if you had to integrate in this case, you would get 3t + c as the varibles are in 't'...

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  103. 1).
    dy/dx=5x^3+2x^2+5

    the integral of that is 5/4x^4+2/3x^3+5x+c

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  104. 2).
    dy/dx=6x+1

    the integral of that is 3x^2+x+c

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  105. 3).
    dy/dx=2

    the integral of that is 2x+c

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  106. 4).
    dy/dx=8x^5-5x^3+4x

    the integral of that is 4/3x^6-5/4x^4+2x^2+c

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  107. 5).
    dy/dx=7x^2+3x+4

    the integral of that is 7/3x^3+3/2x^2+4x+c

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  108. 6).(i) V=7t^2-5t+3

    dv/dt=14t-5

    when t=7

    dv/dt=14(7)-5
    = 98-5
    = 93

    therefore the acc. is 93

    (ii) V=7t^2-5t+3

    the integral of that is 7/3t^3-5/2t^2+3t

    using bounds t=1 and t=4

    [7(4)^3/3-5(4)^2/2+3(4)]-[7(1)^3/5-5(1)^2/2+3(1)]
    [149.33-40+12]-[1.4-2.5+3]
    121.33-1.9
    119.43

    the particle moves 119.43

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  109. 11). y=2x+8/x^2
    y=2x+8x^-2

    dy/dx=2-16x^-3

    d2y/dx2= -48x^-4

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  110. 12). dy/dx= 2x^2-5

    the integral of that is y= 2/3x^3-5x+c

    using the point (3,8) subst in (y)

    8=2(3)^3/3-5(3)+c
    8=18-15+c
    8=3+c
    c=8-3
    c=5

    equation the curve is y=2/3x^3-5x+5

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  111. 8) A curve has equation y = 4/(2)^.5, find dy/dx

    ??????????????
    i don't understand how you're suppose to find the differential of this equation wrt x if there is no x in the entire equation...is this a trick question or am i missing something important????
    *sigh* :(

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  112. 9). dy/dx=16/x^3
    dy/dx=16x^-3

    the integral of that is y= 24x/x^2+c

    using the point (1,4) subst in (y)

    4=24/(1)^2+c
    4=24+c
    c=4-24
    c= -20

    so therefore the equation of the curve is
    y=24/x^2-20

    ReplyDelete
  113. 10)

    y = 6theta - 2sin theta, find dy/dx
    let x = theta
    y = 6x - 2sinx
    dy/dx = 6 - 2cosx
    therefore dy/dx = 6 - 2cos theta

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  114. (8) y=4/(2)^.5
    y=4(2)^-1/2
    dy/dx= -2(2)^-3/2
    miss a try a thing tell me if that correct

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  115. The equation of a curve is y = 2x + 8/x^2, find dy/dx and d^2ydx^2

    y = 2x + 8/x^2
    y = 2x + 8x-2
    dy/dx = 2 + (8*-2)x^(-2-1)
    dy/dx = 2 - 16x^-3

    when dy/dx = 2 - 16x^-3
    d^2ydx^2 = (-16*-3)x^(-3-1)
    d^2ydx^2 = 48x^-4

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  116. badman_nerd how can u find dy/dx if there's is no mention of x in the entire equation????? :(

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  117. #9:
    dy/dx = 16/x³
    in order to obtain the curve, the gradient must be integrated:
    y = ∫ (dy/dx) dx
    y = ∫ 16/x³ + c
    y= ∫ 16x-³
    y = 8x-² + c OR y = 8/x² + c
    substitute point ( 1,4) to find c:
    4 = -8/x^2+c
    4= -8/1+c
    4+8=c
    c=12
    there the equation of the curve is y=-8/x^2+12

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  118. 12. A curve is such that dy/dx = 2x^2 -5. Given that the point (3,8) lies on the curve, find the equation of the curve.

    y = ∫2x^2 - 5
    y = [2x^(2+1)]/3 - 5x + c
    y = 2x^3/3 - 5x + c

    substitute the points (3,8) into the equation to find c

    8 = 2(3)^3/3 - 5(3) + c
    8 = 18 - 15 + c
    8 = 3 + c
    c = 8 - 3
    c = 5

    therefore the equation of the cirve is:
    y = 2x^3/3 - 5x + 5

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  119. 5. dy/dx = 7x^2 + 3x + 4
    y=(7/3)x^3+(3/2)x^2 + 4x

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  120. 3)dy/dx=2

    the integral of that = 2x+c

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  121. 2)dy/dx=6x+1

    the integral of that = 3x^2+x+c

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  122. 11). y=2x+8/x^2
    y=2x+8x^-2

    dy/dx=2-16x^-3

    d2y/dx2= -48x^-4

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  123. 1. y = 6x^3 + 4x^2 - 5x
    dy/dx=18x^2+8x-5

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  124. need some help for number 12!!!!!!

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  125. 1.
    y = 6x^3 + 4x^2 - 5x
    dy/dx=18x^2+8x-5

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  126. 4.
    y=3x^4+3(x^2 + 5)
    dy/dx=12x^3+6x

    ReplyDelete
  127. question 1
    y = 6x^3 + 4x^2 - 5x
    dy/dx=18x^2+8x-5

    ReplyDelete
  128. question 5
    dy/dx = 7x^2 + 3x + 4
    y=(7/3)x^3+(3/2)x^2 + 4x

    ReplyDelete
  129. question 11
    y=2x+8/x^2
    y=2x+8x^-2

    dy/dx=2-16x^-3

    d2y/dx2= -48x^-4

    ReplyDelete
  130. question 12
    dy/dx= 2x^2-5

    the integral of that is y= 2/3x^3-5x+c

    using the point (3,8) subst in (y)

    8=2(3)^3/3-5(3)+c
    8=18-15+c
    8=3+c
    c=8-3
    c=5

    equation the curve is y=2/3x^3-5x+5

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  131. question 11
    y=2x+8/x^2
    y=2x+8x^-2

    dy/dx=2-16x^-3

    d2y/dx2= -48x^-4

    ReplyDelete
  132. qeustion 4

    y = 3x^4 + 3(x^2 +5)
    y=3x^4+3x^2+15
    dy/dx=12x^3+6x

    ReplyDelete
  133. question 2
    2. dy/dx = 6x + 1
    integral of (6x + 1)
    =[6x^(1+1)/2] + 1x
    =6x^2/2 + 1x
    =3x^2 + 1x

    ReplyDelete
  134. question 6
    v = 7t^2 - 5t +3
    v=7t^3/3-5t^2/2+3x+c

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  135. i stand to be corrected for the above answers!!!!!

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  136. for ques 4.

    dy/dx = 8x^5 - 5x^3 + 4x
    y=(8x^6/6)-(5x^4/4)+(4x^2/2)+c
    y=(4x^6/3)-(5x^4/4)+(2x^2)+c

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  137. for ques 7 #4

    y = 3x^4 + 3(x^2 + 5)
    y=(3x^4)+(3x^2)+(15)
    dy/dx =(12x^3)+(6x)

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  138. 2 INTEGRATION

    dy/dx = 6x + 1
    y = 6x^2/2 + x
    y = 3x^2 + x

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  139. 7 1)

    y = 6x^3 + 4x^2 - 5x
    dy/dx = 3(6x^2) + 2(4x) - 5
    dy/dx = 18x^2 + 8x - 5

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  140. for ques 1.

    dy/dx = 5x^3 + 2x^2 + 5
    y=(5x^4)+(2x^3/3)+(5x)+c

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  141. for ques 5
    dy/dx = 7x^2 + 3x + 4
    y=(7/3)x^3+(3/2)x^2 + 4x

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  142. ques 12

    dy/dx = 2x^2 - 5
    y = 2x^2+1/3 - 5x
    y = 2x^3/3 - 5x

    the eq'n of the curve is
    y=2x^3/3 - 5x

    ReplyDelete
  143. The integral of dy/dx = 5x^3 + 2x^2 + 5
    = 5x^4/4 + 2x^3/3 + 5x + c

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  144. The integral of dy/dx = 6x + 1
    = 6x^2/2 + 1x +c

    ReplyDelete
  145. The integral of dy/dx = 8x^5 - 5x^3 + 4x
    = 8x^6/6 - 5x^4/4 + 4X^2/2 + c

    ReplyDelete
  146. The integral of dy/dx = 7x^2 + 3x + 4
    = 7x^3/3 + 3x^2/2 + 4x +c

    ReplyDelete
  147. y = 6x^3 + 4x^2 - 5x
    using y =anx^n-1
    dy/dx = 18x^2 + 8x - 5

    ReplyDelete
  148. 7)
    1. y = 6x^3 + 4x^2 - 5x
    dy/dx = 18x^2 + 8x - 5

    ReplyDelete
  149. 7)
    2. y = x^-3 + 16
    dy/dx = -3x^-4
    dy/dx = -3/x^4

    ReplyDelete
  150. 7)
    4. y = 3x^4 + 3(x^2 + 5)
    y = 3x^4 + 3x^2 + 15
    dy/dx = 12x^3 + 6x

    ReplyDelete
  151. 7)
    5. y + 6 = 4x + 9y - 3x^2
    y - 9y = 4x - 3x^2 - 6
    -8y = 4x - 3x^2 - 6
    y = (4x - 3x^2 - 6)/-8
    y = 4x/-8 + 3x^2/8 + 3/4
    y = x*-2^-1 + 3x^2*8^-1 + 3*4^-1
    dy/dx = -x/(-2^-2) - 3x^2/(8^2) - 3/(4^2)
    dy/dx = -x/4 -3x^2/64 - 3/16

    ReplyDelete
  152. 1. dy/dx = 5x^3 + 2x^2 + 5
    int dy/dx = int 5x^3 + 2x^2 + 5
    = 5x^4/4 + 2x^3/3 +5x +c
    y = 5/4x^4 + 2/3x^3 +5x +c
    where c is the constant of proportionality

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  153. 2. dy/dx = 6x + 1
    int dy/dx = int 6x+1
    = 6x^2/2 +x +c
    y = 3x^2 + x +c

    ReplyDelete
  154. question 1

    the integral of
    dy/dx=5x^3+2x^2+5

    y=(5/4)x^4+(2/3)x^3+5x+c

    ReplyDelete
  155. question 2

    the integral of dy/dx=6x+1

    y=(6/2)x^2+x

    =3x^2+x+c

    ReplyDelete
  156. question 3

    the integral of dy/dx=2

    y=2x+c

    ReplyDelete
  157. question 4

    the integral of dy/dx=7x^2+3x+4

    y=(7/3)x^3+(3/2)x^2+4x+c

    ReplyDelete
  158. question 5

    the integral of dy/dx=8x^5-5x^3+4x

    y=(8/6)x^6-(5/4)x^4+(4/2)x^2+c

    =(4/3)x^6-(5/4)x^4+2x^2=c

    ReplyDelete
  159. question 12

    the integral of dy/dx=2x^2-5

    y=(2/3)x^3-5x+c

    at the point (3,8)

    8=(2/3)(3)^3-5(3)+c
    8=18-15+c
    8=3+c
    8-3=c
    c=5

    equation of the curve y=(2/3)x^3-5x+5

    ReplyDelete
  160. question 10

    y=6 theta-2sin theta

    dy/dtheta=6-2cos theta

    ReplyDelete
  161. #7 (1)
    Y=6X^3+4X^2-2x
    dy/dx=18x^2+8x-5

    ReplyDelete
  162. question 11

    y=2x+8/x^2

    y=2x+8x^-2

    dy/dx=2-16x^-3

    =2-16/x^3

    d^2y/dx^2=48x^-4

    48/x^4

    ReplyDelete
  163. question 7

    part 1

    y=6x^3+4x^2-5x

    dy/dx=18x^2+8x-5

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  164. #7(4)
    y= 3x^4+3(x^2+5)
    dy/dx= 3x^4+3x^2+15
    dy/dx= 12x^3+6x

    ReplyDelete
  165. #7(5)
    y+6=4x+9y-3x^2
    dy/dx=4x+9y-3x^2-6
    dy/dx=4+9-6x
    =13-6x

    ReplyDelete