SOLUTION: Please help me. How to get all the zeros of this polynomial function f(x)=x^3+2x^2-22x

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Question 899365: Please help me. How to get all the zeros of this polynomial function f(x)=x^3+2x^2-22x
Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
How to get all the zeros of this polynomial function 
    %22f%28x%29%22%22%22=%22%22x%5E3%2B2x%5E2-22x

           x%5E3%2B2x%5E2-22x%22%22=%22%22%220%22
           x%28x%5E2%2B2x-22%29%22%22=%22%22%220%22

Use the zero-factor property:

     x+=+0     x%5E2%2B2x-22%22%22=%22%22%220%22
                         x+=+%28-b+%2B-+sqrt%28+b%5E2-4ac+%29%29%2F%282a%29+
                         x+=+%28-%282%29+%2B-+sqrt%28+%282%29%5E2-4%281%29%28-22%29+%29%29%2F%282%281%29%29+
                         x+=+%28-2+%2B-+sqrt%284%2B88%29%29%2F2+
                         x+=+%28-2+%2B-+sqrt%2892%29%29%2F2+
                         x+=+%28-2+%2B-+sqrt%284%2A23%29%29%2F2+ 
                         x+=+%28-2+%2B-+2sqrt%2823%29%29%2F2+
                         x+=+%282%28-1+%2B-+sqrt%2823%29%29%29%2F2+
                         x+=+%28cross%282%29%28-1+%2B-+sqrt%2823%29%29%29%2Fcross%282%29+
                         x+=+-1+%2B-+sqrt%2823%29+

f(x) has three zeros :



Edwin