SOLUTION: write a polynomial function in standered for that has zeros of -1,3i, and 4

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Question 1174335: write a polynomial function in standered for that has zeros of -1,3i, and 4
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
factors are (x+1) and (x-4)
If 3i is a solution, so is -3i
x-3i=0
x=3i
x^2=-9
so the factor is x^2+9
the polynomial is (x^2-3x-4)(x^2+9)
=x^4-3x^3-4x^2+9x^2-27x-36
=x^4-3x^3+5x^2-27x-36
graph%28300%2C300%2C-10%2C10%2C-100%2C100%2Cx%5E4-3x%5E3%2B5x%5E2-27x-36%29