Use the direct method to evaluate : (2a+3) (2a−3) - Vidyadip

Question

Use the direct method to evaluate : $(2a+3) (2a−3)$

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Answer

Note : $(a+b) (a−b) $
$= a^2 − b^2(2a+3) (2a−3) $
$= (2a)^2 − (3)^2$
$= 4a^2− 9$

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