If x^2 + 1/x^2 = 9, what is the value of x^4…

If x^2 + 1/x^2 = 9, what is the value of x^4 + 1/x^4 ?

This problem repeats another one in the library (at most with different numbers), so it's left out of browsing.

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #66439