Evaluate :{(7.8)2−(2.2)2}
{(7.8)2−(2.2)2}=(7.8+2.2)(7.8−2.2)=10.0×5.6=56 Ans.
1.2 + 2.22 + 3.22 + ā¦ + n.2n = (n ā 1) 2n+1 + 2