Tuesday, December 1, 2009

math (1201) - Quad: + and x of roots

from now on im going to use * instead of x for multiplication, should be easier to understand without mixing it up with x-axis and all that crap, computer nerds would understand.. these are my notes anyway.

so the proof of this comes frooooommm..

ax^2 + bx + c = 0

what if we dont want the a there?

then its:

x^2 + (b/a)x + c/a = 0

coz that a is always annoying to work with, at least if its not 1

the deal is, we know the roots, lets call em A and B, multiply to get c and add to achieve b

so.. if you wanna get the sum of A and B, it'd be equal to the b value over the a value, aka -b/a, catch it?

i forget why its minus though, but oh wellers, i missed a fraction of the lesson

and to find the product, its c/a

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