Question

If x=root 2 + 1 find (x-1/x)^2

Answer 1

Answer:

if x=√2+1

√2+1-1/√2

so √2 cancel by√2 and +1 cancel by -1

and answer is 0

Answer 2

Answer:

$x = \sqrt{2} + 1 \\ x - \frac{1}{x} {}^{2} \\ \sqrt{2 } + 1 - \frac{1}{ \sqrt{2} + 1} {}^{2} \\ \sqrt{2} + 1 - \frac{ {1}^{2} }{ { \sqrt{2 { }^{2} } + 1}^{2} } \\ \sqrt{2 } + 1 - \frac{1}{2 + 1 } \\ \sqrt{2} + 1 - \frac{1}{3 } \\ \sqrt{2} + 1 - 1 \div 3 \\ \sqrt{2} + 0 \div 3 \\ \sqrt{2} \div 3 \\ \frac{ \sqrt{2} }{3}$