Question

simplify the following
$(a + b)^2 - (a - b) ^{2}$
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Answer 1

Answer:

(a+b)² - (a-b)²  = 4ab

Step-by-step explanation:

We will use the identity x² - y² = (x+y) (x-y)

In question, x = a+b and y = a-b

So, (a+b)² - (a-b)² = (a + b + a - b)(a + b - (a -b))

= (2a)(a + b - a + b) = 2a × 2b = 4ab

∴ (a+b)² - (a-b)²  = 4ab