1.

2 answers:

7 0

$\left(\sqrt x - \sqrt{3y} \right) \left(\sqrt x + \sqrt{3y} \right)\\\\=\left(\sqrt x\right)^2 - \left(\sqrt{3y} \right)^2\\\\=x -3y$

anzhelika [568]3 years ago

4 0

x - 3y

Solving Stepwise:

$\hookrightarrow \sf \left(\sqrt{x}-\sqrt{3y}\right)\left(\sqrt{x}+\sqrt{3y}\right)$

$\sf apply \ the \ rule : \bold{\left(a-b\right)\left(a+b\right)=a^2-b^2}$

$\hookrightarrow \sf \left(\sqrt{x}\right)^2-\left(\sqrt{3y}\right)^2$

$\hookrightarrow \sf x-3y$

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