can someone give me harder factorising questions..? (1 Viewer)

RealiseNothing · Mar 15, 2012

$a^4 + 4b^4$

$\sqrt{a^4} = a^2$

and

$\sqrt{4b^4} = 2b^2$

Hence we can rewrite the equation as:

$(a^2 + 2b^2)^2 - 4a^2b^2$

We subtract the last term since it's not in the original equation when you expand the brackets. Using difference of two squares:

$(a^2 + 2b^2 + 2ab)(a^2 + 2b^2 -2ab)$

We can use the same technique as before, we notice they are all in standard form except they have an extra $b^2$ :

$[(a+b)^2 +b^2] [(a-b)^2 + b^2]$

The last step isn't necessary, but I like to do it anyway.

girlworld_club · Mar 15, 2012

why did u minus 4a^2-b^2

D94 · Mar 15, 2012

girlworld_club said:
why did u minus 4a^2-b^2

If you expand $(a^2 + 2b^2)^2 - 4a^2b^2$ out and compare it to the question, you will get an extra $4a^2b^2$ , hence why you need to minus it from the new expression.

gurmies · Mar 15, 2012

Factorise x^5 + x^4 + 1

girlworld_club · Mar 15, 2012

i don't get it what's the answer.

Spiritual Being · Mar 15, 2012

Looking at this shit and thanking god because of how simple my life is.

can someone give me harder factorising questions..? (1 Viewer)

RealiseNothing

what is that?It is Cowpea

girlworld_club

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D94

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gurmies

Drover

girlworld_club

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Spiritual Being

hehehehehe

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