If (a2+1)22a−1=x+iy find the value of x2+y2.
Given that : (a2+1)22a−1=x+iy
⇒ (a2+1)2(2a−i)=x+iy⇒ (a2+1)2(2a+i)(2a−i)(2a+i)=x+iy⇒ (a2+1)2(2a+i)4a2+1=x+iy⇒ 2a(a2+1)24a2+1 and y=(a2+1)24a2+1∴ x+y2=4a2[(a2+1)24a2+1]2+[(a2+1)24a2+1]2=(4a2+1)(a2+1)4(4a2+1)2=(a2+1)4(4a2+1)