SOLUTION: Use the quadratic formula to solve 2x^6 - 3x^3 - 8 = 0. Write your answer correct to 3 significant figures.

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Question 1186255: Use the quadratic formula to solve 2x^6 - 3x^3 - 8 = 0. Write your answer correct to 3 significant figures.
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
it will be x^3=(1/2a)(-b+/- sqrt (b^2-4ac)
think of this as let z=x^3. so the equation becomes 2z^2-3z-8=0
=(1/4)(3+/- sqrt(9+64))
=(1.4)(3+/- sqrt(73)
=2.89, -1.39
the answer is the cube root of each of those, since we solved for x^3/z
x=-1.11, 1.42
graph%28300%2C300%2C-3%2C3%2C-5%2C5%2C2x%5E6-3x%5E3-8%29