Question

if a = 2 under root 2 + 1 then find the value of a minus 1 by a

Answer 1

a=2
so, √1-a
=√1-2 = -1

Answer 2

Hello Mate!

$a = 2 \sqrt{2} + 1 \\ \frac{1}{a} = \frac{1}{2 \sqrt{2} + 1} \\ rationalize \\ \frac{1}{2 \sqrt{2} + 1} \times \frac{2 \sqrt{2} - 1 }{2 \sqrt{2} - 1} \\ \frac{2 \sqrt{2} - 1}{8 - 1} \\ \frac{2 \sqrt{2} - 1}{7}$

2_/2 + 1 - ( 2_/2 - 1 ) /7
( 14_/2 + 7 - 2_/2 + 1 ) /7
( 12 _/2 + 8 ) / 7

Hope u got it☺
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