Question

x+1/x=-1 then the value of x^3-1/x3 is​

Answer 1

Answer:

x + 1/x = -1

then x^3 + 1/x^3

by using formula a^3 + b^3 = (a+b) ( a^2 -ab +b^2)

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

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

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

=-1{(x+1/x)^2 -2} -1

=2