The number of solutions of sin2x+(2+2x-x2)sinx-3(x-1)2=0, where -π≤x≤π, is _________. [2024]
(2)
We have sin2x+(2+2x-x2)sinx-3(x-1)2=0 where -π≤x≤π
⇒sin2x+(3-(x-1)2)sinx-3(x-1)2=0
⇒sinx(sinx+3)-(x-1)2(sinx+3)=0
⇒(sinx+3)(sinx-(x-1)2)=0
⇒sinx+3≠0⇒sinx-(x-1)2=0⇒sinx=(x-1)2
There are two points of intersection.
So, number of solutions are 2.