Expand: (x+1x)2
x2−1x2+2
x2+1x2−2
x2+1x2+2
x2+1x+2
Using the identity, (a+b)2=a2+b2+2ab we get, (x+1x)2 = x2+(1x)2+2×x×1x =x2+1x2+2
Evaluate ∫1(1−x2)√1+x2 dx