Question

The ratio of the areas bounded by the curves $y = \cos x$ and $y = \cos 2x$ between $x = 0,$ $x = \pi/3$ and $x -$axis, i

• A. $\sqrt{2}:1$
• B. $1:1$
• C. $1:2$
• D. $2:1$

Answer 1

Answer: (D)

$2:1$

Answer 2

$A_{1} = \int_{0}^{\pi/3}{\cos xdx = \frac{\sqrt{3}}{2}}$, $A_{2} = \int_{0}^{\pi/3}{\cos 2xdx = \frac{\sqrt{3}}{4}}$

∴ $A_{1}:A_{2} = 2:1$.