Lf x+1/x=12 then find the value of x3+1/x3

Explanation:

First we find what x is:
x + 1/x = 12
x + 1 = 12x
1 = 12x - x
1 = 11x
1/11 = x
Or x = 1/11

Plug x value in x^3 + 1/x^3

(1/11)^3 + 1/(1/11)^3
= (1^3/11^3)+ 1/(1^3/11^3)
= (1/1331 + 1)/1/1331
= (1/1331 + 1331/1331)/1/1331
= 1332/1331 x 1331/1
= 1332/1
= 1332

Therefore, x^3 + 1/x^3 = 1332