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Polynomials maths question (1 Viewer)

kaz1

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Solve x^4 + x^3 + x^2 - 5x - 2 = 0

i spent a whole hour on it with the factor theorem and cant find the answer
 
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x^4 + x^3 + x^2 - 5x - 2 = 0

are you sure the signs are the right way around? you pretty much can't factorise that (not easily anyway)
 

morganforrest

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There really has to be more information. Maybe if they gave us one of the factors, or the roots....or something. But there really isn't enough information to factorise that, even at an Ext maths level...and this is a school certificate quesiton :confused:
 

boblemur

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lol hey soz to cheat :p but i put it into mathcad 14 and it said the resault was too large to display(ie its a really really fucked up awnser) :p so if the nerds who made math cad cant do it :p i doubt its a yr 10 question :p

so ur missing some info find that info from ur teacher or wat eva :) and im sure it will end up not being too bad
 
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I've just tried every trick I'm supposed to know in yr12 ext2, and I got nothing.

So the question is probably wrong.
 

Lufa

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correct me if im wrong

p(-1)=-1^4+-1^3+-1^2-5*-1-2=0

therefor a factor of it is x+1
then u can work out the second factor with the first factor
 
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Lufa said:
correct me if im wrong

p(-1)=-1^4+-1^3+-1^2-5*-1-2=0

therefor a factor of it is x+1
then u can work out the second factor with the first factor
p(-1) = 1 - 1 + 1 + 5 - 2 = 4, not zero. p(1) doesnt work either and either one should work.

there's maybe a typo in the question?
 

kaz1

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i think the teacher wrote the question wrong. i'll ask her tomorrow
 

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