The correct option is B (n2+a2)yn
Given,y=easin−1x
On differentiating w.r.t x, we get
y1=easin−1xa.1¯¯¯¯¯¯¯¯¯¯¯1−x2
⇒y1¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯1−x2=ay
⇒1−x2y21=a2y2
Again, differentiating w.r.t x, we get
(1−x2)2y1y2−2xy12=a22yy1
⇒(1−x2)y2−xy1−a2y=0
Using Leibntiz's rule,
(1−x2)yn+2+nc1yn+1(−2x)+nc2y2(−2)−xyn+1−nc1yn−a2yn=0
⇒(1−x2)yn+2+xyn+1(−2n−1)+yn[−n(n−1)−n−a2]=0
⇒(1−x2)yn+2−(2n+1)xyn+1=(n2+a2)yn