Question

How do you simplify (√5+9√2)(4√5−√2)?

Answer 1

$\large\bf{ \underline{ \underline{Answer \: : }}}$

$\red{ = ( \sqrt{5} + 9 \sqrt{2} )(4 \sqrt{5} - \sqrt{2} )} \\ \\ \red{ = 20 - 18 }\\ \\ \red{ = 2}$

Answer 2

$( \sqrt{5} + 9 \sqrt{2} )(4 \sqrt{5} - \sqrt{2} ) \\ \\ \sqrt{5} (4 \sqrt{5} - \sqrt{2} ) + 9 \sqrt{2} (4 \sqrt{5} - \sqrt{2} ) \\ \\ 4 \times 5 - \sqrt{10} + 36 \sqrt{10} - 9 \times 2 \\ \\ 20 - 1 \sqrt{10} + 36 \sqrt{10} - 18 \\ \\ 2 + 35 \sqrt{10}$