Question

plzz answer this question​

Answer 1

Answer:

2

Step-by-step explanation:

Since,a=1+√2

Therefore,

$a - \frac{1}{a} = \frac{ {a}^{2} - 1 }{a} \\ = \frac{ {(1 - \sqrt{2} )}^{2} - 1 }{1 - \sqrt{2} } \\ = \frac{ 1 - 2 \sqrt{2} + 2 - 1}{1 - \sqrt{2} } \\ = \frac{ 2 - 2 \sqrt{2} }{1 - \sqrt{2} } \times \frac{1 + \sqrt{2} }{1 + \sqrt{2} } \\ = \frac{2(1 - \sqrt{2})(1 + \sqrt{2} )}{1 - 2} \\ = \frac{2(1 - 2)}{(1 - 2)} \\ = 2$

Hope it helps ❣️❣️