Hello is this right? Form a polynomial f(x) with real coheficients having the given degree and zeros. zeros: -1,3i. degree 3 I got x^3+x^2-9x-9. thank you so much
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Originally Posted by girl1985 Hello is this right? Form a polynomial f(x) with real coheficients having the given degree and zeros. zeros: -1,3i. degree 3 I got x^3+x^2-9x-9. thank you so much did you mean to type 3 instead of 3i? if not, you're wrong. the function you gave has the zeros -1, 3, -3
Thank you jhevon. So what would be the answer?
Originally Posted by girl1985 Hello is this right? Form a polynomial f(x) with real coheficients having the given degree and zeros. zeros: -1,3i. degree 3 I got x^3+x^2-9x-9. thank you so much Assuming it is a polynomial in R[x] (over the reals). Then if 3i is a solution then so is -3i. That means all the polynomials are: K(x+1)(x-3i)(x+3i) Where K is a non-zero constant polynomial. Multiply those factors, K(x^3+x^2+9x+9) It seems thou are wrong.
Originally Posted by girl1985 Thank you jhevon. So what would be the answer? x^3 + x^2 + 9x + 9, you had a -9x and -9, they should have been +, do you see where you made your mistake?
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