Algebra and indices

[xinying-812]

HELP! My friend ask me this question
If x + 1/x = 9...
Then find the value of x⁴+ 1/x⁴ without finding the value of x.


Thank you so much

 

[stapel]

If x + 1/x = 9...
Then find the value of x⁴+ 1/x⁴ without finding the value of x.

What are your thoughts? What have you tried? How far have you gotten? Where are you stuck?

Please be complete. Thank you!

 

[Deleted member 4993]

HELP! My friend ask me this question
If x + 1/x = 9...
Then find the value of x⁴+ 1/x⁴ without finding the value of x.


Thank you so much

Hint:

(a + b)⁴ = a⁴ + b⁴ -2a²b² + 4ab(a+b)²