If Sin-1x2-x43+x69-……..+cos-1x4-x83+x129-….=π2 where O≤x<3, then the number of values of x is
0
1
2
3
We have
x21+x23=x41+x43sin−1x+cos−1x=π2
3x23+x2=3x43+x4
x23+x4=x43+x2
x23+x4−3x2−x4=0
x=0, x2=1
x=±1