How do I factor these problems

x^3-2x^2-4x-8

x^7y^2-4x^5yy^2-21x^3y^2

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]How do I factor these problems

x^3-2x^2-4x-8

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This one is not easily factorable. It has 2 complex roots.

Are you sure you don't mean

Otherwise, as you have it, the factorization is(which I pumped out with Maple):

Quote:

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x^7y^2-4x^5yy^2-21x^3y^2

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Is this what you mean:

?

The y I have highlighted. I suppose it's errant?

If this is correct, then factor out :



Factor in the parentheses by letting



Resub:

If you mean x^3 - 2x^2 - 4x + 8, then this equals
x^2(x-2) - 4(x-2) = (x^2 - 4) (x-2) = (x+2)(x-2)^2