Question
Evaluate:
$(218)^2- (217)^2$
$(218)^2- (217)^2$
✓
Answer
We have,
$(n + 1)^2- n^2= (n + 1) + n$
Taking $n = 140$ and $(n + 1) = 141$
We get,
$(218)^2- (217)^2= (218 + 217) = 435$
$(n + 1)^2- n^2= (n + 1) + n$
Taking $n = 140$ and $(n + 1) = 141$
We get,
$(218)^2- (217)^2= (218 + 217) = 435$
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