Mathematics
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OpenStudy (thefluffmuncher):
Can someone help me with this?
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satellite73 (satellite73):
first factor over the real numbers
do you recognize it as a perfect square?
OpenStudy (thefluffmuncher):
I'm not really good with the technical terminology
satellite73 (satellite73):
a perfect square means some expression squared, like \[(2+x)^2\]
satellite73 (satellite73):
it is always the case that \[(a+b)^2=a^2+2ab+b^2\]
you have something that looks very much like \[a^2+2ab+b^2\]in your expression \[x^2+10x^2+25\]
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satellite73 (satellite73):
oops i meant in \[x^4+10x^2+25\]
OpenStudy (thefluffmuncher):
idk the teacher always told me to start by finding the GCF
OpenStudy (thefluffmuncher):
so it's \[(x+5)^{2}\] ?
satellite73 (satellite73):
close
it is \[(x^2+5)^2\]
OpenStudy (thefluffmuncher):
is that because of the x^4?
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satellite73 (satellite73):
right
satellite73 (satellite73):
so now you are done factoring with real numbers
for complex numbers, do you know how to solve \[x^2+5=0\]?
OpenStudy (thefluffmuncher):
you take the square root of them?
satellite73 (satellite73):
first, subtract \(5\) from both sides
OpenStudy (thefluffmuncher):
okay
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satellite73 (satellite73):
then take the square root
don't forget the \(\pm\)
OpenStudy (thefluffmuncher):
\[x=i \pm \sqrt{5}\]
OpenStudy (thefluffmuncher):
like that?
satellite73 (satellite73):
no not quite
satellite73 (satellite73):
\[x^2=-5\\
x=\pm\sqrt{-5}\\
x=\pm\sqrt{5}i\]
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OpenStudy (thefluffmuncher):
the i is separate from 5 right?
satellite73 (satellite73):
yes, outside, not under the radical
satellite73 (satellite73):
now that you have the zeros, you factor \[x^2+5=(x+\sqrt5 i)(x-\sqrt5 i)\]
OpenStudy (thefluffmuncher):
omg thanks so much :)
satellite73 (satellite73):
yw, don't forget to write your final answer
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OpenStudy (thefluffmuncher):
\[\left\{ x+\sqrt{5}i , x-\sqrt{5}i \right\}\]