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LOLS me again (1 Viewer)

super.muppy

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someone please do (t-2)^3+(t+2)^3
Factor as fully as possible

I really did try

TY in advance
 

supercalamari

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I'm SO glad I'm not doing maths this year, 160/180 kids in my year are already freaked out by their work... I know this doesn't answer your question, hope the smarter kids here can help you out.
 

duckcowhybrid

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Let t-2=x
Let t+2=y

Therefore, you have

x^3 + y^3
= (x + y)(x^2 - xy + y^2) Now sub in original values

= (t-2 + t+ 2)(t^2 - 4t + 4 - (t^2 -4) + t^2 + 4t + 4)

= 2t(t^2 + 12)

And thats it. Not hard really, except typing it out on a computer. Same asnwer as above, but with working.
 

bored of sc

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someone please do (t-2)^3+(t+2)^3
Factor as fully as possible

I really did try

TY in advance
It's an addition of two cubes.

I.e. a3+b3 = (a+b)(a2-ab+b2) but a = t-2 and b = t+2.

So (t-2)3+(t+2)3
= [(t-2)+(t+2)][(t-2)2-(t-2)(t+2)+(t+2)2]
= above answers

Just realised...
 

Miss Sunshine

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bored of sc is right

it is the sum of two cubes

you need to know the rule
 

lolokay

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you could also just expand them both
 

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