BMI229
Can someone please give me an example of a sum of cubes equation...Please



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mathstudent55
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Can you do complex (imaginary) solutions, or only real solutions?

BMI229
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I just need an example worked out all the way.

mathstudent55
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x^3 + 27 = 0

mathstudent55
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Notice that 27 = 3^3, so this is the sum of the cube of x and the cube of 3.
x^3 + 3^3 = 0
The first step is to factor it.

mathstudent55
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(x + 3)(x^2  3x + 9) = 0

BMI229
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Thanks bro

mathstudent55
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Now to solve the equation, do
x + 3 = 0 or x^2  3x + 9 = 0
The left side is x = 3.
For the right side, use the quadratic formula.

mathstudent55
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wlcm