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# Factor Theorem watch

1. how do I use the factor theorem to show that (x+10) is a factor of f(x)=2x^3=x^2-166x+240 ?
2. so what do you know about the factor theorem?
3. Set x+10 = 0 so x = -10
Then sub -10 into f(x) so you can find f(-10), if the answer is zero it shows that x + 10 is a factor as there are no remainders
4. (Original post by hpblcparaboloid)
so what do you know about the factor theorem?
nothing. literally nothing...
5. (Original post by _princessxox)
Set x+10 = 0 so x = -10
Then sub -10 into f(x) so you can find f(-10), if the answer is zero it shows that x + 10 is a factor as there are no remainders
Okay that makes sense. thank you x
6. The factor theorem means:

f(x-a) is a factor of f(x) if and only if f(a) = 0

In this instance to prove that (x+10) is a factor, consider that, and substitute -10 into that equation, and if your final answer turns out to be 0, (x+10) is a factor of the polynomial.
7. (Original post by useless_mind)
nothing. literally nothing...
Then it's probably a good idea to look it up before you ask for help with it.

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