Question

x3 +1/x3=110 then find x+1/x

Answer 1

we will find this answer by trial and error method
so ,

x³+1/x³ = 110
x³+1/x³+3(x+1/x) = 110+3(x+1/x). { add 3(x+1/x) to both sides}
(x+1/x)³ = 110+3(x+1/x)


let (x+1/x) = 4
(4)³ = 110+3(4)
64 ≠ 110+12 => 64 ≠ 124

let (x+1/x) = 5

(5)³ = 110+3(5)
125 = 110+15
=> 125 = 125
therefore , answer Is 125
hope this helps