Question

Find the slope of tangent to the curve y = 2 cos²(3x) at `x = π/6`.

Answer 1

`dy/dx = 2 xx 2 xx cos(3x) xx (-sin 3x) xx 3`

`dy/dx = 6 sin 6x`

`dy/dx]_(x = π/6) = -6 sin π`

= – 6 × 0

= 0