Question

find the value of x^3+1/x^3 if x^2+1/x^2=4​

Answer 1

Answer:

x^2+1/x^2=4

(x+1/x)^2-2x1/x=4

(x+1/x)^2=4+2=6

x+1/x=√6

x^3+1/x^3

=(x+1/x)^3-3x.1/x(x+1/x)

=(√6)^3-3.√6

=6√6-3√6=3√6