Question

Find the 45th derivative of y = cos(2x)

Answer 1

Explanation:

y=cos2x

y1=-2sin2x=2cos(2x+π/2)

y2=-2*2sin (2x+π/2)=2²cos(2x+π/2+π/2)=2²cos(2x+2*π/2)

y3==2²*-2sin(2x+2*π/2)=2³cos(2x+2*π/2+π/2)=2³cos(2x+3π/2)

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y45=2^{45}cos(2x+45π/2)