SOLUTION: what is the polynomial function in standard form with zeros -1, 3 and 4?

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: what is the polynomial function in standard form with zeros -1, 3 and 4?       Log On


   

Question 1005153: what is the polynomial function in standard form with zeros -1, 3 and 4?
Found 2 solutions by fractalier, vleith:
Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
You use the zeroes to make the factors and set their product to zero, or
(x+1)(x-3)(x-4) = 0
such that
f(x) = (x+1)(x-3)(x-4)
f(x) = x^3 - 6x^2 + 5x + 12

Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
you are told the zeroes, so you need to start with that
f%28x%29+=+%28x%2B1%29%28x-3%29%28x-4%29
Now start to expand
f%28x%29+=+%28x%5E2+-3x+%2B+x+-3%29%28x-4%29
f%28x%29+=+%28x%5E2+-2x+-3%29%28x-4%29
f%28x%29+=+x%5E3+-4x%5E2+-2x%5E2+%2B+8x+-3x+%2B+12
f%28x%29+=+x%5E3+-+6x%5E2+%2B+5x+%2B+12
See the entire solution here --> http://www.wolframalpha.com/input/?i=%28x%2B1%29%28x-3%29%28x-4%29&dataset=