Respuesta :

Answer:

The answer is 123.

Step-by-step explanation:

Given that-

( [tex]x + \frac{1}{x}[/tex] ) = 3.....................(i)

To find -

( [tex]x^{5} + \frac{1 }{x^{5} }[/tex] ) = ?

Now squaring both sides of equation (i)-

( [tex]x^{2}  + \frac{1}{x^{2} } + 2[/tex] ) = 9

( [tex]x^{2} + \frac{1}{x^{2} }[/tex] ) = 7....................(ii)

On cubing equation (i) both sides-

( [tex]x^{3} + \frac{1}{x^{3} } + 3 ( x + \frac{1}{x} )[/tex] ) = 27

( [tex]x^{3} + \frac{1}{x^{3} } + 3 * 3[/tex] ) = 27

( [tex]x^{3} + \frac{1}{x^{3} }[/tex] ) = 27 - 9

( [tex]x^{3} + \frac{1}{x^{3} }[/tex] ) = 18.....................(iii)

Multiply equation (i)  and equation (ii)-

( [tex]x^{2} + \frac{1}{x^{2} }[/tex] )  ( [tex]x^{3} + \frac{1}{x^{3} }[/tex] ) = 7 × 18

( [tex]x^{5} + \frac{1}{x^{5} } )+ ( x + \frac{1}{x} )[/tex] = 126

( [tex]x^{5} + \frac{1}{x^{5} } ) = 126 - 3

( [tex]x^{5} + \frac{1}{x^{5} } ) = 123