SOLUTION: What are the zeros of x^4-2x^3-23x^2-2x-24

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Question 742446: What are the zeros of x^4-2x^3-23x^2-2x-24
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E4-2x%5E3-23x%5E2-2x-24=0 write -2x%5E3 as 4x%5E3-6x%5E3,
-23x%5E2 as %2Bx%5E2-24x%5E2
x%5E4%2Bx%5E2%2B4x%5E3%2B4x-6x%5E3-6x-24x%5E2-24=0.....group
%28x%5E4%2Bx%5E2%29%2B%284x%5E3%2B4x%29-%286x%5E3%2B6x%29-%2824x%5E2%2B24%29=0.factor
x%5E2%28x%5E2%2B1%29%2B4x%28x%5E2%2B1%29-6x%286x%5E2%2B1%29-24%28x%5E2%2B1%29=0
%28x%5E2%2B4x-6x-24%29%28x%5E2%2B1%29=0
%28x-6%29%28x%2B4%29%28x%5E2%2B1%29=0
solutions:
if x-6=0 => x=6
if x%2B4=0 => x=-4
if x%5E2%2B1=0 => x%5E2=-1 => x=sqrt%28-1%29=> x=i or x=-i

+graph%28+600%2C+600%2C+-10%2C+10%2C+-300%2C+50%2C+x%5E4-2x%5E3-23x%5E2-2x-24%29+