中4 maths come!!!!!!!!!!
when p(x)is divided by (x^2)+1, the remainder is 2x+3.given p(0)=0
find the remainder when p(x) is divided by x((x^2)+1) :):victory::loveliness::kiss: :o:P:$:@ :Q:L:sleepy::funk: :hug::time::dizzy::shutup: 本帖最後由 火中有火 於 24-3-2012 22:22 編輯
Answer係咪 -3x^2+2x ?
你肯定條數係比左'x^2+1'你?
因為真係好怪
搞到我剩係識屈一個合理的p(x)出來試...
eg. p(x)=(x^2 + 1)(x^2 - 3) + (2x + 3) ←符合p(x)=0
=x^4 - 2x^2 + 2x
=x(x^3 - 2x + 2)
=(x^3 + x)x - 3x^2 + 2x
eg.p(x)=(x^2 + 1)(x - 3) + (2x + 3) ←符合p(x)=0
=x^3 - 3x^2 + 3x
=(x^3 + x) - 3x^2 + 2x
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↓平時做開果d係咁的↓
The remainder is 9 when f(x) is divided by x-5 and
the remainder is -5 when f(x) is divided by x+2.
Find the remainder when f(x) is divided by (x+2)(x-5)
Let the remainder be px+q
f(5)=5p+q=9 and f(-2)=-2p+q=-5
...
p=2 and q=-1
The remainder is 2x+1
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如果係你打錯題目搞到我做咁耐的話我會殺左你 好了今日日討論完有正解
做 polynomial 的 long division 要知道一點
when the divider is of degree n, the highest possible degree of the remainder is n-1
ie. when the divider is of degree 3, the highest possible degree of the remainder is 2
我地又知道如果x-a係factor的話,咁p(a)=0
同埋the remainder is p(b) when p(x) is divided by (x-b)
呢條題目的divider係degree 3
我地可以 let the remainder be px^2+qx+r, where p,q and r are constants.
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p(0)=p*0^2+q*0+r=0
r=0
p(i)=pi^2+qi+r=2i+3
-p+qi+0=2i+3
-p+qi=3+2i
p=-3 and q=2
The remainder is -3x^2+2x when p(x) is divided by x^3+x.
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不過都係想講多次粗口...因為真係冇見過咁的題目...
粗口粗口粗口粗口粗口粗口粗口粗口粗口粗口......... :kiss:good:kiss: 其實呢ｄ我好多唔得了
順手借位一下
:):dizzy::curse::)
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