Q. The number of ordered pairs $(x,y)$ satisfying $y = 2\sin{x\ and\ y = 5x^{2} + 2x + 3}$ is
A) 0
B) 1
C) 2
D) $\infty$
Explanation
(a)
$2\sin{x = 5x^{2} + 2x + 3}$
$\Rightarrow \ 2\sin{x = 4x^{2} + (x + 1)^{2} + 2}$
But $2\sin{x \leq 2}$
and $4x^{2} + (x + 1)^{2} + 2 > 2$, so it has no solution
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.