MHB How can I solve radical equations using the given hint?

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To solve the radical equation sqrt{x^4 - 13x^2 + 37} = 1, substitute x^2 with t, transforming the equation into t^2 - 13t + 36 = 0 after squaring both sides. This allows for factoring and finding the values of t, which are then back-substituted to find x. It's crucial to check all potential solutions due to the possibility of extraneous roots introduced by squaring. The process is straightforward, involving standard algebraic techniques. Ultimately, following these steps leads to the correct solutions for the equation.
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Determine all of the real number solutions for the radical equation.

sqrt {x^4 - 13x^2 + 37} = 1

Hint given in textbook:

Let x^2 = t and x^4 = t^2

After applying the hint given, do I proceed as usual by squaring both sides?

I have to back-substitute somewhere in the solution steps, right?

Why is it important to always check the answer (s) when dealing with radical equations?
 
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Yes, it is solving as usual.
You can square both sides, then subtract 1 from both sides.
Factor as usual. Substitute back in.

Try it out and see if you get the correct answers.
 
joypav said:
Yes, it is solving as usual.
You can square both sides, then subtract 1 from both sides.
Factor as usual. Substitute back in.

Try it out and see if you get the correct answers.

Great. Ok. It's not so bad.
 
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