Divided Polynomials
\[(x^{2}+3x+2)\div(x+2)\]
\[(y^2+7y+10)\div(y+5)\]
do you know how to factor (x^2 +3x+2)?
no i dont know how to do any of this :/
to factor x^2 + 3x + 2, you need to find two numbers that multiply to 2 (last term) and add to 3 (middle coefficient) those two numbers are 1 and 2 since 1*2 = 2 and 1+2 = 3 This means x^2 + 3x + 2 factors to (x+1)(x+2)
so... \[\large \frac{x^2+3x+2}{x+2}\] \[\large \frac{(x+1)(x+2)}{x+2}\] \[\large \frac{(x+1)\cancel{(x+2)}}{\cancel{x+2}}\] \[\large x+1\]
so that would be your answer for the first one x+1?
yep, you got it
so the idea is to step 1) factor everything as much as possible step 2) cancel the common factors
okay so can you break this one down for me please like you did the first one? \[\frac{ 2x^4-13x^3+16x^2-9x+20 }{ x-5 }\]
you will have to use polynomial long division here or synthetic division
idk how to do that can you do it step by step so i can see how to do it?
have you ever done polynomial long division before?
no sir!
hmm ok one sec
can you do the second question that i posted at the top ?
I recommend reading this lesson here http://www.purplemath.com/modules/polydiv2.htm
what do you get when you factor y^2+7y+10
(y+1)(y+2)
no
you need to find two numbers that multiply to 10 and add to 7
there are no numbers?
you sure?
list the possible ways to factor 10 and see which pairs add to 7
5 and 2?
so it factors to (y+5)(y+2)
so your answer would be y+2?
yep
okay so now can you help me solve the one i posted like 5 mins ago up top the longer one?
\[(20x^3-8x^2+5x-5)\div(5x-2)\]
like I said, you use polynomial long division I recommend reading that lesson
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