SOLUTION: solve: 8x^3+8x+5/2x-1

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Question 862295: solve: 8x^3+8x+5/2x-1
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

8x^3+8x+5/2x-1

Using synthetic division for x = -1/2

-0.5	8	0	8	5

		-4	2	-5

	8	-4	10	0

(x+.5)(8x^2 - 4x + 10)

       x+=+%284+%2B-+sqrt%28+304%29%29%2F%2816%29+ 

       x+=+%284+%2B-+sqrt%28+16%2A19%29%29%2F%2816%29+ 

       x+=+.25+%2B-+.25sqrt%2819%29 

One real root x = -.5  and two imaginary .25 ± .25√19