Question

Evaluate:

(218)² – (217)²

Answer 1

Given (218)² – (217)²

According to the property 8 i.e. for every natural number n, we have [(n+1)²-n²] = [(n+1) + n]

Here n = 217 By applying the above property we get,

=(218)² – (217)² 

= (217+1) + 217 

= 218 + 217 

= 435