Question
Evaluate the following using identities:
$(2\text{x} +\text{y})(2\text{x} - \text{y})$
$(2\text{x} +\text{y})(2\text{x} - \text{y})$
✓
Answer
We have,
$(2\text{x} +\text{y})(2\text{x} - \text{y})$
$= (2\text{x})^2 - (\text{y})^2 $ $\begin{bmatrix}\because(\text{a}+\text{b})(\text{a}-\text{b})=\text{a}^2-\text{b}^2\\\text{Where}\ \text{a}=2\text{x}\ \text{and}\ \text{b}=\text{y}\end{bmatrix}$
$=4\text{x}^2-\text{y}^2$
$(2\text{x}+\text{y})(2\text{x}-\text{y})=4\text{x}^2-\text{y}^2$
$(2\text{x} +\text{y})(2\text{x} - \text{y})$
$= (2\text{x})^2 - (\text{y})^2 $ $\begin{bmatrix}\because(\text{a}+\text{b})(\text{a}-\text{b})=\text{a}^2-\text{b}^2\\\text{Where}\ \text{a}=2\text{x}\ \text{and}\ \text{b}=\text{y}\end{bmatrix}$
$=4\text{x}^2-\text{y}^2$
$(2\text{x}+\text{y})(2\text{x}-\text{y})=4\text{x}^2-\text{y}^2$
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