Question

x²+x = 5. The find the value of (x+3)³ + (1/(x+3))³.

Answer 1

Answer:

110

Step-by-step explanation:

First, let's find the value of (x+3) + 1/(x+3)

=> {(x+3)² + 1}/(x+3)

=> (x²+6x+10)/(x+3)

=> (5x+15)/(x+3)    {From given eqn -- x²+x =5}

=> 5

Now,

(x+3)³ + 1/(x+3)³ = {(x+3) + 1/(x+3)}³ -3*(x+3)(1/(x+3))[(x+3) + 1/(x+3)]

(x+3)³ + 1/(x+3)³ = 5³- 3*5 = 125 - 15 = 110