Question

Hii please solve the problem in notebook

Answer 1

Hi...☺

Here is your answer...✌

USING IDENTITY

$(a - b)(a+ b) = {a}^{2} - {b}^{2} \\ \\ We \: have, \\ \\ (3 \sqrt{5} - 4 \sqrt{2} )(3 \sqrt{5} + 4 \sqrt{2} ) \\ \\ = {(3\sqrt{5} )}^{2} - {(4 \sqrt{2} )}^{2} \\ \\ = {3}^{2}\times { (\sqrt{5}) }^{2} - {4}^{2} \times {(\sqrt{2} )}^{2} \\ \\ = 9 \times 5 - 16 \times 2 \\ \\ = 45 - 32 \\ \\ = 13$