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Old November 7th, 2009, 08:13 AM
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Default Finding the root question

1. Calculate the greatest root of 2x^3-4x^2-3x+1=0, to three decimal places.Show all steps
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Old November 7th, 2009, 09:00 AM
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See here: The Cubic Formula

Plug in your a=2, b=-4, c=-3, d=1 into that cumbersome formula.

Yes, there is a formula (like the quadratic formula) for cubics. It is rather large by comparison, but will work.
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Old November 7th, 2009, 02:04 PM
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Quote:
Originally Posted by shane99 View Post
1. Calculate the greatest root of 2x^3-4x^2-3x+1=0, to three decimal places.Show all steps
The fact that a decimal approxiation is required suggests that you're meant to use technology (graphics calculator, CAS, whatever you've been taught to use). Most likely, graph y = 2x^3-4x^2-3x+1 and use the technology to get the largest x-intercept.
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