Number of roots

JEE Advanced 2015 Preparation › Algebra questions › Number of roots

Prove the following statement to be true:
The polynomial p(x)=(ax²+bx+x)(ax²+dx-c),ac is not equal to zero,has exactly two roots

#Mathematics #Algebra

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9 Answers

39

Dr.House ·2011-03-07 23:32:21

can u check the question once?

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Vinay Arya ·2011-03-07 23:36:28

Ohh.Sorry.The polynomial is p(x)=(ax²+bx+c)(ax²+dx-c).

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Joydoot ghatak ·2011-03-14 21:22:31

u mean we r to prove that the polynomial has 2 repeated roots.. ??? :-o

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Vinay Arya ·2011-03-15 02:52:18

Two same roots mean only one root.It has exactly two roots.

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Joydoot ghatak ·2011-03-15 03:47:41

you must see it is a 4 degree polynomial... so 4 roots...
isnt it???

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36

rahul ·2011-03-15 04:05:27

consider any 4 degree expression having zeroes -1,-1,-2,-2

clearly, the equation has 2 roots as 2 pairs are repeated...!!

i guess this is what he wanna say..!!

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Vinay Arya ·2011-03-16 03:54:36

Please show me how are these zeroes.How are these satisfying the polynomial?I can't see that these are satisfying it.

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36

rahul ·2011-03-16 06:13:35

oh my god... that was a reply for joydoot...!!

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Vinay Arya ·2011-03-16 07:48:51

Sorry I did not see the word "consider".

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