Question:
The area of the region:
$R=\left\{(x, y): 5 x^{2} \leq y \leq 2 x^{2}+9\right\}$ is :
Correct Option: , 2
Solution:
Required area $=2 \int_{0}^{\sqrt{3}}\left(2 x^{2}+9-5 x^{2}\right) d x$
$=2\left[9 x-x^{3}\right]_{0}^{\sqrt{3}}$
$=2[9 \sqrt{3}-3 \sqrt{3}]=12 \sqrt{3}$