#Quadratic problem

27 messages · Page 1 of 1 (latest)

polar plover
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Im unsure how to simplify to this point can someone explain?

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Is the final part in completing the square form?

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i've put it in completing the square form and its closer to the answer

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where have i gone wrong because the parts outside the square do not equate

wide galleon
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Hint: ||How do you get z^2 from z?||

dry flint
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Not sure if this will help but x^2 - 19y^2 is the field norm of Z[sqrt(19)],i.e. Elements of the form x +ysqrt(19) where x, y integers

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I. E. I. E. w*conj(w), where conj(w) is x - yswrt(19)

wide galleon
dry flint
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yeah probs not

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Was just wondering if there was a neat trick involving that lol

wide galleon
dry flint
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you don't nead to even do that p sure thonk

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just plug in for z and expand

wide galleon
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Substitution for z will work too I suppose.

dry flint
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Both sides

polar plover
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i probably should've made that more clear

polar plover
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my steps so far were to square x² - 19y²

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then expand that to x⁴ - 38x²y² + 361y⁴

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from there I recognised that the answer equation is in the form (ax² + b)² + c and thats similar to the (ax + b)² + c form of completing the square

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im not quite sure how to complete the square on polynomials larger than 2

polar plover
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okay i did some research

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.close

idle rockBOT
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Solved

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