Question

rationalise the denominator 4/
​3+2√​5

Answer 1

Hey friend,
Here is the answer you were looking for:
$\frac{4}{3 + 2 \sqrt{5} } \\ \\ on \: rationalizing \: the \: denominator \: we \: get \\ \\ = \frac{4}{3 + 2 \sqrt{5} } \times \frac{3 - 2 \sqrt{5} }{3 - 2 \sqrt{5} } \\ \\ using \: the \: identity \\ (a + b)(a - b) = {a}^{2} - {b}^{2} \\ \\ = \frac{4 \times 3 - 4 \times 2 \sqrt{5} }{ {(3) }^{2} - (2 \sqrt{5}) } \\ \\ = \frac{12 - 8 \sqrt{5} }{9 - 20} \\ \\ = \frac{12 - 8 \sqrt{5} }{-11}$

Hope this helps!!!

@Mahak24

Thanks...
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