Given that z , n , p stand for the number of non-real, negative and non-negative roots of the equation 2 0 1 4 x 2 0 1 4 + 3 0 2 1 x 1 0 0 6 − 4 0 2 8 x = 0 , find the value of ( z × 3 p ) 2 0 1 4 ( m o d 1 0 0 0 0 )
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This problem makes use of Signs logic/rules which are easy to catch from the above explanation (hopefully ) :D
Note that the real numbers are a subset of the complex numbers. Thus, there are 2014 complex roots.
I've updated the phrasing of the problem to reflect what you intended.
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Thanks for that! The wording nearly killed me! :D
Great application of Decartes' Rule of Signs!!
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Thank you very much :) ...Did you do it the same way too?
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I used a calculator for about 15 min to calculate the remainder, hence I bashed this out with a calculator.
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@Ronak Agarwal – LOL Hope you didnt use it for the 1st part :P
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The problem is a simple application of Descartes' rule of signs
Lets take this poly to be f ( x ) = 2 0 1 4 x 2 0 1 4 + 3 0 2 1 x 1 0 0 6 − 4 0 2 8 x .
We find that it can be factored to 1 0 0 7 x ( 2 x 2 0 1 3 + 3 x 1 0 0 5 − 4 ) . Thus one root is x = 0 .
Let g ( x ) = 2 x 2 0 1 3 + 3 x 1 0 0 5 − 4
∙ g ( x ) has 1 sign change, in the coefficient changing from 3 to − 4 . Thus g ( x ) has 1 positive root and including 0, there are 2 ⟹ p = 2
∙ g ( − x ) = − 2 x 2 0 1 3 − 3 x 1 0 0 5 − 4 , this has 0 sign changes, to give us 0 negative roots.
∙ Thus it has 2 0 1 2 complex roots. (2014 total roots-2 positive real roots) ⟹ z = 2 0 1 2
Now all we gotta do is to simply simplify the above expression 1 2 0 7 2 2 0 1 4 ( m o d 1 0 0 0 0 ) which is a piece of cake using Euler's totient theorem.
Answer is 2 9 4 4
If you liked my solution-Kindly upvote it. :)