Question

using a sutable identity evalute the following (99

Answer 1

Heya!

(99)² can be written as (100-1)(100-1)

I.e., (100-1)²

which is in the form of (a-b)²

• (a-b)²=a²+b²-2ab

Here a= 100 , b =1

>> (100)²+(1)²-2(100)(1)

>> 10000+1-200

>> 10001 - 200

>> 9801 is the answer .

Hope it helps!