Question

By using the formula evaluate (198)

Answer 1

Evaluate the square of 198 Do it like this. 198^2= (200-2)^2 = 200^2 -2x200x2 + 2^2 = 40000 -800 +4 = 32004 { by using ( a-b)^2 = a^2 -2ab - b^2

Answer 2

If you want to find the square of 198, i.e., (198)², then it would go like this:
(198)²
(200-2)²                             (Because 200-2=198)
(a-b)²=a²+b²-2ab
Here, a is 200 and b is 2(not -2)
Then,
[(200)²+(2)²-(2*200*2)]
(40000+4-800)
40004-800
39,204       <-------Answer.


Check:
198*198=39,204

Thus, the answer is 39,204.