Question

please tell me the answer with full explanation ​

Answer 1

Solution : -

x³ + 1/x³ = 110

Formula :-

(x + 1/x)³ = x³ + 1/x³ + 3(x + 1/x)

So ,

(x + 1/x)³ - 3(x + 1/x) = 110

Let :-

x + 1/x = W

then

W³ - 3W - 110 = 0

When we put , w = 5

Then , (5)³ - 3(5) - 110

125 - 15 - 110

125 - 125 = 0

Therefore , 5 is satisfying this equation .

then W = 5

So , x + 1/x = 5