Question

please tell this answer class 9 icse​

Answer 1

Answer:

$x + \frac{1}{x} = \frac{ 34 + 20 \sqrt{2} }{5 + 2 \sqrt{2} }$

Step-by-step explanation:

$x = \frac{1}{5 + 2 \sqrt{2} } \\ x + \frac{1}{x} \\ = \frac{1}{5 + 2 \sqrt{2} } + \frac{1}{ \frac{1}{5 + 2 \sqrt{2} } } \\ = \frac{1}{5 + 2 \sqrt{2} } + 5 + 2 \sqrt{2} \\ = \frac{1 + {(5 + 2 \sqrt{2} )}^{2} }{5 + 2 \sqrt{2} } \\ = \frac{1 + 25 + 8 + 20 \sqrt{2} }{5 + 2 \sqrt{2} } \\ = \frac{ 34 + 20 \sqrt{2} }{5 + 2 \sqrt{2} }$