We have to find number of terms in the expansion of [(a+b)2+(a−b)2]2 ⇒[(a+b)2+(a−b)2]2=(a2+2ab+b2+a2−2ab+b2)2 =[2(a2+b2)]2 =4(a2+b2)2 As we know the total number of terms in the expansion of (x+y)n is n+1 Here n=2 Therefore, total number of terms is 2+1=3.