Using the formula for squaring a binomial, evaluate the (78)2.

1.	Using the formula for squaring a binomial, evaluate the (78)2.
Answer» Given (78)² But we can write 78 as 80-2 And also we know that (a – b)²= a²-2ab+b² By applying the above identity we get (78)²= (80-2)²= 80²-2(80) (2) +2² (80-2)²=6400-320+4=6084

Answer»

Given (78)²

But we can write 78 as 80-2

And also we know that (a – b)²= a²-2ab+b²

By applying the above identity we get

(78)²= (80-2)²= 80²-2(80) (2) +2²

(80-2)²=6400-320+4=6084

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