Question

If x-1/x=7,find x² +1/x²​

Answer 1

answer for this question is 51

Answer 2

$x - \frac{1}{x} = 7$

squaring

$(x - \frac{1}{x} ) {}^{2} = 7 {}^{2}$

$x {}^{2} + ( \frac{1}{x} ) {}^{2} - 2 \times \times \frac{1}{x } = 49$

$x {}^{2} + \frac{1}{x {}^{2} } - 2 = 49$

$x {}^{2} + \frac{1}{x {}^{2} } = 49 + 2 = 51$