Question

Can someone solve this ? thank you !

Answer 1

Answer:

Step-by-step explanation:

14)

$\frac{3}{\sqrt{7}}=\frac{3*\sqrt{7}}{\sqrt{7}*\sqrt{7}}\\\\=\frac{3\sqrt{7}}{7}$

15a)

$\frac{5}{\sqrt{2}}=\frac{5*\sqrt{2}}{\sqrt{2}*\sqrt{2}}\\\\=\frac{5\sqrt{2}}{2}$

b)(x + y)² - (x - y)² = 4xy

(2 + √3)² - (2 -√3)² = 4* 2 * √3

                              = 8√3