Find the square root of
1+a2+(1+a2+a4)12
It can be written as 1+a2+(1+a2+a4)12
=1+a2+√1+a2+a4
=1+a2+√1+a4+2a2−a2
=1+a2+√(1+a2)2−(a)2
=1+a2+2√1+a2−a2×1+a2+a2
=1+a+a22+1+a2−a2+2√1+a2−a2×1+a2+a2
=(1+a+a22+1+a2−a2)2
Hence square root of 1+a2+(1+a2+a4)12 is 1+a+a22+1+a2−a2.