SOLUTION: x^3+125=0

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Question 650800: x^3+125=0
Found 2 solutions by Edwin McCravy, ewatrrr:
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
x³ + 125 = 0
 x³ + 5³ = 0
(x + 5)(x² - 5x + 25) = 0

x + 5 = 0;  x² - 5x + 25 = 0
    x = -5;            x = %28-%28-5%29+%2B-+sqrt%28%28-5%29%5E2-4%2A%281%29%2A%2825%29+%29%29%2F%282%2A%281%29%29+
                       x = %285+%2B-+sqrt%2825-100+%29%29%2F2+
                       x = %285+%2B-+sqrt%28-75%29%29%2F2+
                       x = %285+%2B-+i%2Asqrt%2875%29%29%2F2+
                       x = %285+%2B-+i%2Asqrt%2825%2A3%29%29%2F2+
                       x = %285+%2B-+5i%2Asqrt%283%29%29%2F2+
                       x = %285%281+%2B-+i%2Asqrt%283%29%29%29%2F2+

Three solutions: -5, %285%281+%2B+i%2Asqrt%283%29%29%29%2F2+, %285%281+-+i%2Asqrt%283%29%29%29%2F2+ 

Edwin

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

x^3+125=0

 x^3 = -125

x+=+root%283%2C-125%29

    x = -5



and -5%2A-5%2A-5+=+-125