Home » (frac{d}{dx}) cos(3x(^2) – 2x) is equal to

(frac{d}{dx}) cos(3x(^2) – 2x) is equal to

(frac{d}{dx}) cos(3x(^2) – 2x) is equal to

  • A.
    -sin(6x – 2)
  • B.
    -sin(3x2 – 2x)dx
  • C.
    (6x – 2) sin(3x2 – 2x)
  • D.
    -(6x – 2)sin(3x2 – 2x)
Correct Answer: Option D
Explanation

Let (3x^{2} – 2x = u)

(y = cos u implies frac{mathrm d y}{mathrm d u} = – sin u)

(frac{mathrm d u}{mathrm d x} = 6x – 2)

(therefore frac{mathrm d y}{mathrm d x} = (6x – 2) . – sin u)

= (- (6x – 2) sin (3x^{2} – 2x))

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