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polynomials (1 Viewer)

ozidolroks

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can someone please explain how i can do this question ?

I have the method but i don't understand it

When a polynomial P(x) is divided by x^2-4 the remainder is 2x+3. What is the remainder when P(x) is divided by x-2.


Thankx
 

lyounamu

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can someone please explain how i can do this question ?

I have the method but i don't understand it

When a polynomial P(x) is divided by x^2-4 the remainder is 2x+3. What is the remainder when P(x) is divided by x-2.


Thankx
P(x) = (x^2-4)Q1(x) + 2x+3 ...(1)
P(x) = (x-2)Q2(x) + a

From (1) when x=2, P(2) = 7
From (2) when x=2, P(2) = a
so a= 7

remainder is 7
 

Asubmarine

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P(x)=(x^2-4)Q(x)+2x+3
=(x+2)(x-2)Q(x)+2x+3
therefore P(x)/(x-2) = (x+2)Q(x)+(2x+3)
Remainder=2x+3
as (x-a) is (x-2) a=2
then R =2(2)+3=7
 

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