Question

If a+1÷a=5 find the value of a3+1÷a3

Answer 1

Solution:

Given:-

a+1/a = 5

We have to find:-

a³+1/a³

As we know that,

(a+1/a)³= a³+1/a³+3(a+1/a)

⟹ (5)³=a³+1/a³+3(5)

⟹ 125 = a³+1/a³+15

⟹ 125 / 15 = a³+1/a³

⟹ 25 / 3 = a³+1/a³

⟹ 8.33 = a³+1/a³

Thus, the value of a + 1 / a³ = 8.33

Note :-

The value of a + 1 / a³ is taken till two Decimal places.