Can anyone tell me how to factor polynomials?

Question

A few examples please?

Answer 1

wow its been a long time.. i use a calculator to do that now.. but here goes one thing i remember...

lets say we have a polynomial like this

x^2 -3x-10 and we need to factor it..

we take a look at what factors of -10 we could use that would add up to -3 in this case there are two way to get -10 (-2*5) or (2*-5) if we add the two sets together one gives us -3 and the other gives us 3 so we can throw out the -2*5 terms.

So now we lay out the factors.... we need two x's to get x^2 so we need two x's in the first terms (remember FOIL?)

lay the terms out so they give us the correct values

(x+2)(x-5) now we can use FOIL (firs, outer, inner, last) to check ourselves...
X*X = x^2
X*-5 = -5X
2*x =2x
2*-5=-10

so we get [x^2] +[-5x] +[2x] +[-10]
or x^2 -5x+2x-10
combine like terms now
-5x+2x =-3x

which gives us
x^2-3x-10

hope that helps