Answer:
x = ±1, ±√65
Explanation:
You want the solution to (x² -1)³ = 64(x² -1)².
Solution
Subtracting the right side, we have ...
(x² -1)³ -64(x² -1) = 0
(x² -1)²(x² -1 -64) = 0
Zero product rule
The solutions make the factors zero:
x² -1 = 0 ⇒ x = ±1
x² -65 = 0 ⇒ x = ±√65
Solutions are x = ±1 and x = ±√65.
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Additional comment
The solutions ±1 are each multiplicity 2.