Question

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

Answer 1

Ответ:

$(3 \sqrt{5} - 2) \times (3 \sqrt{5} + 2) = {(3 \sqrt{5}) }^{2} - {2}^{2} = {3}^{2} {( \sqrt{5}) }^{2} - {2}^{2} = 9 {( \sqrt{5} )}^{2} - {2}^{2} = 9 \times 5 - {2}^{2} = 45 - 4 = 41$