SOLUTION: need help find all real and complex solutions: x^3+2x^2+3x=0

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Question 62775: need help
find all real and complex solutions: x^3+2x^2+3x=0
Answer by Cintchr(481) About Me  (Show Source):
You can put this solution on YOUR website!
+x%5E3%2B2x%5E2%2B3x=0+
factor out an x
+x%28x%5E2%2B2x%2B3%29=0+
the Trinomial will not factor, so use the Quadratic equation
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
a=1
b=2
c=3
x+=+%28-2+%2B-+sqrt%28+2%5E2-4%2A1%2A3+%29%29%2F%282%2A1%29+
work what is under the root first
x+=+%28-2+%2B-+sqrt%28+4-4%2A1%2A3+%29%29%2F%282%2A1%29+
x+=+%28-2+%2B-+sqrt%28+4-12+%29%29%2F%282%2A1%29+
x+=+%28-2+%2B-+sqrt%28+-8+%29%29%2F%282%2A1%29+
Work the denominator
x+=+%28-2+%2B-+sqrt%28+-8+%29%29%2F2+
work the negative root
x+=+%28-2+%2B-+2i+%28sqrt%28+2+%29%29%29%2F2+
reduce the fraction
x+=+%28-1+%2B-+1i+%28sqrt%28+2+%29%29%29%2F1+
x+=+-1+%2B-+1i+%28sqrt%28+2+%29%29+
This is 2 of your answers, the other is x=0 .... the one we factored out at the beginning.