SOLUTION: -15x+2x^3-x^2

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Question 534464: -15x+2x^3-x^2
Found 2 solutions by madhan_math, Alan3354:
Answer by madhan_math(34) About Me  (Show Source):
You can put this solution on YOUR website!
Given equation can be written as
2x^3-x^2-15x=0.
i.e., x[2x^2-x-15]=0

x=0, 2x^2-x-15=0

To solve this quadratic equation we follow the steps
1) multiply the coefficient of x^2 and constant term = -30
2) Now we split -30 as product of two numbers and if we add that two numbers we get the coefficient of x.
i.e., -30 = (-6)x(5)
3) 2x^2-6x+5x-15=0 ==> 2x(x-3)+5(x-3)=0
4) 2x+5=0, x-3=0
5) x=-5/2, x=3
Finally we get the roots of x are x=0,3,-5/2

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
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