Question

find the value the number

Answer 1

√(√2-1)/(√2+1)
=√(√2-1)(√2-1)/(√2+1)(√2-1)
=√(√2-1)^2/2-1
=√(2+1-2√2)
=√3-2√2

Answer 2

Hello Mate!

$\frac{ \sqrt{2} - 1}{ \sqrt{2} + 1} = \frac{ \sqrt{2} - 1}{ \sqrt{2} + 1 } \times \frac{ \sqrt{2} - 1}{ \sqrt{2} - 1 } \\ 2 + 1 - 2 \sqrt{2} = 3 - 2 \sqrt{2} \\ \sqrt{ \frac{ \sqrt{2} - 1 }{ \sqrt{2} + 1} } = \sqrt{3 - 2 \sqrt{2} } \\ \sqrt{2 + 1 - 2 \sqrt{2} } \\ \sqrt{ { \sqrt{2} }^{2} + {1}^{2} - 2 \times 1 \times \sqrt{2} } \\ \sqrt{ {( \sqrt{2} - 1)}^{2} } = \sqrt{2} - 1 \\ \sqrt{2} = 1.41 \\ 1.41 - 1 = 0.4142$

Hope it helps☺!