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April 21st, 2013, 10:39 AM   #1
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Sum & Product of the Roots of a Quadratic Equation

My answer seems relatively close to that of the text book. Can anyone see where I've gone wrong, or does the books answer contain a typo?

Many thanks.

Q. If & are the roots of the equation , form the equation whose roots are & .

Attempt:
Sum of Roots: ...(where
Product of Roots: ...(where


(From text book
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April 21st, 2013, 11:39 AM   #2
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Re: Sum & Product of the Roots of a Quadratic Equation

the answer is (2(x-5)^2-(x-5)-4) = 2x^2-21x+51 = 0.
2x^2-21x+51 isn't an equation so the answer from the textbook is wrong.
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April 21st, 2013, 12:55 PM   #3
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Re: Sum & Product of the Roots of a Quadratic Equation

Hello, bilano99!

Quote:








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April 21st, 2013, 01:22 PM   #4
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Re: Sum & Product of the Roots of a Quadratic Equation

Thank you very much.
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April 21st, 2013, 02:22 PM   #5
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Re: Sum & Product of the Roots of a Quadratic Equation







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April 21st, 2013, 07:08 PM   #6
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Re: Sum & Product of the Roots of a Quadratic Equation

Quote:
Originally Posted by bilano99
. . .
That should be

The required equation is 2(x - 5) - (x - 5) - 4 = 0, i.e., 2x - 21x + 51 = 0.
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