SOLUTION: Find all the solutions to: {{{x^3+1=0}}} Please enter your answer in rectangular form. Thank you.

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Question 983470: Find all the solutions to: x%5E3%2B1=0
Please enter your answer in rectangular form.
Thank you.
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Find all the solutions to: x%5E3%2B1=0
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%28x%2B1%29%2A%28x%5E2+-+x+%2B+1%29+=+0
x = -1
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%28x%5E2+-+x+%2B+1%29+=+0
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B-1x%2B1+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%28-1%29%5E2-4%2A1%2A1=-3.

The discriminant -3 is less than zero. That means that there are no solutions among real numbers.

If you are a student of advanced school algebra and are aware about imaginary numbers, read on.


In the field of imaginary numbers, the square root of -3 is + or - sqrt%28+3%29+=+1.73205080756888.

The solution is , or
Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B-1%2Ax%2B1+%29