Question

please anyone good morning
29​

Answer 1

Heya!

Here is yr answer...

Given, x+1/x = 7

For finding, x^3+1/x^3

Just use, n^2 - 2 formula

Here, n = 7

Now,

=> 7^2 - 2

=> 49 - 2

=> 47

Hope it helps u..

Answer 2

GOOD MORNING!

( a + b )³ = a³ + b³ + 3ab ( a + b )

( x + 1/x )= 7 ... { Given }

CUBING ON BOTH SIDES WE HAVE

( x + 1/x )³ = 7³

x³ + 1/x³ + 3 ( x + 1/x ) = 343

x³ + 1/x³ + 3 ( 7 ) = 343

x³ + 1/x³ = 343 - 21

x³ + 1/x³ = 322

So,

X³ + 1/X³ = 322