Question

x+1/x=3
find the value of

x^3+1/x^3​

Answer 1

Step-by-step explanation:

From question x+1/x=√3

x+1/x=√3

Cubing on both LHS and RHS we get,

(x+1/x)

3

=(√3)

3

X

3

+(1/x

3

)+3(x+(1/x))=3√3

x

3

+1/x

3

+3(√3)=3√3

By transporting we get

x

3

+1/x

3

+3√3−3√3=0

x

3

+1/x

3

=0

Answer 2

$x + 1 = 3x \\ 1 = 3x - x \\ 1 = 2x \\ x = \frac{1}{2} \\ {x}^{3} + \frac{1}{ {x}^{3} } \\ ( { \frac{1}{2}) }^{3} \frac{1}{ \frac{1}{2} } \\ \frac{1}{8} + \frac{2}{1} \\ \frac{17}{8}$