Question
Simplify $(2 a+3 b)^2$.
✓
Answer
$\text {We have, }(2 \text{a}+3 b)^2=(2 \text{a})^2+(3 b)^2+2(2 \text{a} \times 3 b) $ $ \qquad[\because(\text{a}+\text{b})^2=\text{a}^2+2 \text{a} \text{b}+\text{b}^2] $
$ =2 \text{a} \times 2 \text{a}+2 \times 2 \text{a} \times 3 \text{b}+3 \text{b} \times 3 \text{b} $
$=4 \text{a}^2+12 \text{a} \text{b}+9 \text{b}^2$
$ =2 \text{a} \times 2 \text{a}+2 \times 2 \text{a} \times 3 \text{b}+3 \text{b} \times 3 \text{b} $
$=4 \text{a}^2+12 \text{a} \text{b}+9 \text{b}^2$
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