Question

Solve this question
With logical explanation
use identities or formulas
all the best​

Answer 1

$\huge\fbox\blue{⭐Solution⭐}$

$\bf{Open \: \: the \: \: brackets }$

$\: \: \: \: \: \: \: \: \: \: \: \: (3 \sqrt{5} - 5 \sqrt{2}) (4 \sqrt{5} + 3 \sqrt{2} )$

$\bf \: \: \: \: \: = > 3 \sqrt{5} (4 \sqrt{5} + 3 \sqrt{2} ) - 5 \sqrt{2} (4 \sqrt{5} + 3 \sqrt{2} )$

$\bf \: \: \: \: = >3 \sqrt{5} (4 \sqrt{5} ) + 3 \sqrt{5} (3 \sqrt{2} ) - 5 \sqrt{2} (4 \sqrt{5} ) - 5 \sqrt{2} (3 \sqrt{2} )$

$\bf \: \: \: \: \: \: = > 12 \times 5 + 9 \sqrt{10} - 20 \sqrt{10} - 15 \times 2$

$\bf \: \: \: \: \: \: \: \: \: \: \: \: \: \: = > 60 - 11 \sqrt{10} - 30$

$\bf \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: = > 30 - 11 \sqrt{10}$

⭐ Hope you understand this concept mate ⭐