Precalc question please help question posted below
Find a cubic function with the given zeros. \(\sqrt{6}\sqrt{-6}~-3\) \(f(x) = x^3 - 3x^2 - 6x - 18\) \(f(x) = x^3 + 3x^2 - 6x - 18\) \(f(x) = x^3 + 3x^2 + 6x - 18\) \(f(x) = x^3 + 3x^2 - 6x + 18\)
test them out ....
i got the 2nd one @amistre64
are your zeros posted correctly?
yes
sqrt(6) -x sqrt(-6)-x ----------- sqrt(-36) -xsqrt(6) -xsqrt(6) + x^2 ----------------------- sqrt(-36)-2x sqrt(6) + x^2 -3 - x ------------------------ your roots dont match up as is, unless ive made some error
-x^3+(1+i) sqrt(6) x^2-3 x^2+(3+3 i) sqrt(6) x-6 i x-18 i or its negative
again, are your roots posted correctly? -sqrt(6) or is it sqrt(-6) ??
sqrt(-6)
then none of these options work, you have ONE complex root
whoops just looked again it is supposed to be -sqrt
yeah .... thats what i thought, if so then the second one is fine
Thank you!
http://www.wolframalpha.com/input/?i=x%5E3+%2B+3x%5E2+-+6x+-+18 youre welcome
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