Answer:
x = {-2, 0, 2}
Explanation:
You want the solutions to √((√(x²) -1)²) = 1.
Solution
Squaring both sides gives ...
(√(x²) -1)² = 1² = 1
Taking the square root of both sides gives ...
√(x²) -1 = ±1
Adding 1, we have ...
√(x²) = 1 ± 1 = {0, 2}
We know that √(x²) = |x|, so this reduces to ...
|x| = {0, 2}
x = {±0, ±2}
x = {-2, 0, 2}
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Additional comment
For finding the solutions graphically, we like to plot the equation in the form f(x) = 0. The graphing calculator readily identifies the x-intercepts, which are the solutions.