Question

Find the second derivative of y=cos^2(7t)

Answer: 98(sin^2(7t) - cos^2(7t))

Need proper working. ​

Answer 1

Answer:

y = cos²(2x + 1)

y = 1/2 + 1/2cos[2(2x +1)]

y = 1/2 + 1/2cos(4x + 2)

dy/dx = - 1/2sin(4x + 2)(4)

= - 2sin(4x + 2)

d²y/dx² = - 2cos(4x + 2)(4)

= - 8cos(4x + 2)

Step-by-step explanation:

hope it helps (~‾▿‾)~