Question

If x=√2+1,find the value of x²+1/x²

Answer 1

EXPLANATION

Question

x = √2 + 1

TO Find VALUE OF X^2 + 1/X^2

Let x = √2 + 1

therefore,

1/x = 1/√2 + 1

rationalise the value of 1/x

we get,

1/√2 + 1 X √2 - 1 / √2 - 1

√2 - 1 / 2 - 1

√2 - 1 = 1/x

x^2 + 1/x^2

it is in the form of = a^2 + b^2

=> (a + b)^2 - 2ab

(x^2 + 1/x^2 )

(x + 1/x )^2 - 2x*1/x

(√2 + 1 + √2 - 1 )^2 - 2

(2√2 )^2 - 2

8 - 2 = 6 = ANSWER