If x=root2 - 1 then find the value of x^2-1/x

1.	If x=root2 - 1 then find the value of x^2-1/x
Answer» 1/x=1/√2-1. Rationalise the denominator 1/x=1/√2-1×√2+1/√2+1=√2+1Now use the identity (a+b)² i.e (x+1/x)² = (x)²+(1/x)²+2(x)(1/x) Now x in multiplication will cut from each other then: (√2-1)²×(√2+1)²+2 then [(√2)²+(1)²- 2(√2)(1)] [(√2)²+(1)²+2(√2)(1)] +2 then this will be 3- 2√2+ 3+2√2+2 now 2√2will cut from each other then remain will be 3+3+2=8 (ans.)

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