SOLUTION: Solve 2x^3+3x^2+5x+2=0

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Question 1133833: Solve 2x^3+3x^2+5x+2=0
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

2x%5E3%2B3x%5E2%2B5x%2B2=0

2x%5E3%2B2x%5E2%2B4x%2Bx%5E2%2Bx%2B2=0+
%282x%5E3%2Bx%5E2%29%2B%282x%5E2%2Bx%29%2B%284x%2B2%29=0
x%5E2%282x%2B1%29%2Bx%282x%2B1%29%2B2%282x%2B1%29=0
%282+x+%2B+1%29+%28x%5E2+%2B+x+%2B+2%29+=+0
solutions:
if %282+x+%2B+1%29+=+0 =>2x=-1=>x=-1%2F2
if +%28x%5E2+%2B+x+%2B+2%29+=+0
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-1+%2B-+sqrt%28+1%5E2-4%2A1%2A2+%29%29%2F%282%2A1%29+
x+=+%28-1+%2B-+sqrt%28+1-8+%29%29%2F2+
x+=+%28-1+%2B-+sqrt%28+-7+%29%29%2F2+
x+=+%28-1+%2B-+sqrt%28-1%29%2Asqrt%287+%29%29%2F2+
x+=+%28-1+%2B-+i%2Asqrt%287+%29%29%2F2+

=>x+=+%28-1+%2B+i%2Asqrt%287+%29%29%2F2+ or x+=+%28-1+-+i%2Asqrt%287+%29%29%2F2+



+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+2x%5E3%2B3x%5E2%2B5x%2B2%29+