#hard precalc/algebra 2 problem

10 messages · Page 1 of 1 (latest)

weak hill
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the question is sqrt[(√x)+3]=x-3. i've tried every method under the sun: substituting u for √x, squaring both sides twice, even taking the ln and derivatives of both sides (wrong strategy, but i was at my wit's end)

what's more is that my teacher's solution–according to themself btw–is very unintuitive. this is their solution:

I love this question but i cannot for the life of me find a way to crack it

rustic pilotBOT
dusky sigil
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that's probably the most elegant solution

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your method of squaring twice works too tho

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you'd get $x = (x-3)^4 - 6(x-3)^2 + 9$

lilac capeBOT
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Donkey

dusky sigil
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and after that factorize it via hit and trial

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find 1,4 to be the integer roots

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and quadratic formula the rest

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beyond that its a matter of plugging the roots into your original solution to check for extraneous roots