Question

question is given above in the picture please

Answer 1

Hope u like my process
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$\frac{15}{ \sqrt{10} + \sqrt{20} + \sqrt{40} - \sqrt{5} - \sqrt{80} } \\ = \frac{15}{ \sqrt{10} + \sqrt{ {2}^{2} \times 5} + \sqrt{ {2}^{2} \times 10 } - \sqrt{5} - \sqrt{ {4}^{2} \times 5 } } \\ = \frac{15}{ \sqrt{10} + 2 \sqrt{5} + 2 \sqrt{10} - \sqrt{5} - 4\sqrt{5} } \\ = \frac{15}{3 \sqrt{10} - 3 \sqrt{5} } = \frac{5}{ \sqrt{10} - \sqrt{5} } \\ = \frac{5( \sqrt{10} + \sqrt{5} )}{( \sqrt{10} - \sqrt{5} )( \sqrt{10} + \sqrt{5}) } \\ = \frac{5( \sqrt{10} + \sqrt{5} ) }{ {( \sqrt{10} )}^{2} - {( \sqrt{5}) }^{2} } \\ = \frac{5( \sqrt{10} + \sqrt{5}) }{10 - 5} \\ = \frac{5( \sqrt{10} + \sqrt{5}) }{5} \\ = \sqrt{10} + \sqrt{5}$
=3.162 +2.236

=5.398
Hope this is ur required answer
Proud to help you