Question

if x^2+1/x^2=6,find the value of x^4+1/x^4.

Answer 1

${x}^{2} + \frac{1}{ {x}^{2} } = 6$
squaring both sides
${ ({x}^{2} + \frac{1}{ {x}^{2} }) }^{2}$
$= {x}^{4} + \frac{1}{ {x}^{4} } + 2 = 36$
${x}^{4} + \frac{1}{ {x}^{4} } = 36 - 2 = 34$