Question

if x^2+1/x^2=18 find x^3-1/x^3

Answer 1

X^2+1/X^2=18 X^3 -1/x^3

X^2+1=18X^2 =(±1/rt17)^3-1/(±1/tr17)^3

17X^2=1 =1-(1/rt17)^3

X^2=1/17

X=±1/root17