SOLUTION: 2x to the third power + 3x to the second power minus 8x +12 =0

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Question 955965: 2x to the third power + 3x to the second power minus 8x +12 =0
Found 5 solutions by CubeyThePenguin, MathTherapy, timofer, ikleyn, greenestamps:
Answer by CubeyThePenguin(3113) About Me  (Show Source):
You can put this solution on YOUR website!
2x^3 + 3x^2 + 8x + 12 = 0
(2x + 3)(x^2 + 4) = 0

all roots: -3/2, 2i, -2i

real roots: -3/2

Answer by MathTherapy(10719) About Me  (Show Source):
You can put this solution on YOUR website!
2x to the third power + 3x to the second power minus 8x +12 =0

The other person's solutions are correct, if the equation is: 2x%5E3+%2B+3x%5E2+%2B+8x+%2B+12+=+0, as this trinomial factors nicely.
But, what I see is: 2x%5E3+%2B+3x%5E2+-+8x+%2B+12+=+0, which DOESN'T factor nicely. Am I the only one?

Answer by timofer(142) About Me  (Show Source):
You can put this solution on YOUR website!
Spacing of the characters should have meaning.

%282x%29%5E3%2B%283x%29%5E2-8x-12=0
8x%5E3%2B27x%5E2-8x-12=0

Answer by ikleyn(53614) About Me  (Show Source):
You can put this solution on YOUR website!
.

To this visitor, I would recommend to take classes on mathematical writing
equations and expressions, using a computer keyboard, before posting to the forum.

Only after getting a certificate of successful completing such a class,
this visitor can be allowed to post to the forum.



Answer by greenestamps(13295) About Me  (Show Source):
You can put this solution on YOUR website!


... or perhaps the problem is presented in especially bad form and the equation is actually supposed to be

2x%5E3%2B3x%5E2-%288x%2B12%29=0

In this case also the polynomial factors nicely, yielding "nice" answers:

2x%5E3%2B3x%5E2-8x-12=0

x%5E2%282x%2B3%29-4%282x%2B3%29=0

%28x%5E2-4%29%282x%2B3%29=0

Solutions: x=2, x=-2, x=-3/2