Question

The function $y = a(1-\cos x)$ is maximum when x is equal to

• A. $\pi$
• B. $\frac{\pi}{2}$
• C. $-\frac{\pi}{2}$
• D. $-\frac{\pi}{6}$

Hint:

$\cos x$ ranges from $-1$ to $1$.

Answer 1

The Correct Option is A

Step 1: $y = a(1-\cos x)$ is maximum when $\cos x$ is minimum.}
Step 2: $\cos x$ minimum is $-1$ at $x = \pi$. So $y_{max} = a(1-(-1)) = 2a$.}