Question

If x+1/x=5,find the value of x^3+1/x^3

Answer 1

Hey there!

Here's your solution :

We will be using the Identity of ( a + b) ³

Given,

x + 1/x = 5 .

Now,

Cubing on both sides,

( x + 1/x)³ = 5³

x³ + 1/x³ + 3x(1/x) ( x + 1/x) = 125

x³ + 1/x³ = 125 - 3(5)

x³ + 1/x³ = 125-15

x³ + 1/x³ = 110

Hope helped!