Question

Evaluate f(x) = 2Sinx + cos(2x) if x =π/5

Answer 1

Answer:$f(\frac{\pi}{5})=1.485$Explanations:

The given function is:

f(x) = 2 sinx + cos (2x)

Since x = π/5, substitute π/5 into the given function.

$\begin{gathered} f(\frac{\pi}{5})=\text{ 2 sin(}\frac{\pi}{5})+\cos \text{ (}\frac{2\pi}{5}) \\ f(\frac{\pi}{5})\text{ = }2(0.588)\text{ + }0.309 \\ f(\frac{\pi}{5})\text{ = }1.176+0.309 \\ f(\frac{\pi}{5})\text{ = }1.485 \end{gathered}$