Find the divisor in each of the following:
1) Dividend=3x^2+4x-7, quotient=x+2, remainder= -3
MY ANSWER: x-(2/3)
2) Dividend=-4x^2+12x-2, quotient=2x-1, remainder=3

thx

我既答案同書既答案完全唔同... 唔知點解..
thx

---

3) When a polynomial f(x) is divided by 2x^2-x+3, the quotient and the remainder are 8x-3 and 4 respectively. Find remainder when f(x) divided by 1-4x

tridentenviro :Find the divisor in each of the following:
1) Dividend=3x^2+4x-7, quotient=x+2, remainder= -3
MY ANSWER: x-(2/3)
2) Dividend=-4x^2+12x-2, quotient=2x-1, remainder=3

thx

我既答案同書既答案完全唔同... 唔知點解..
thx

介唔介意講下你本書個 answer 出黎 ~

AVD1 :

tridentenviro :Find the divisor in each of the following:
1) Dividend=3x^2+4x-7, quotient=x+2, remainder= -3
MY ANSWER: x-(2/3)
2) Dividend=-4x^2+12x-2, quotient=2x-1, remainder=3

thx

我既答案同書既答案完全唔同... 唔知點解..
thx

介唔介意講下你本書個 answer 出黎 ~

1 ) 3x-2
2 ) -2x+5

Division algorithm:
Dividend = Quotient × Divisor + Remainder

1.
3x²+4x－7 = (x+2) × Divisor－3
3x²+4x－4 = (x+2) × Divisor
Divisor = (3x²+4x－4) / (x+2)

然後用Long division或者Synthetic division計 (3x²+4x－4) ÷ (x+2)

就會計到Divisor = 3x－2

JY4066 :Division algorithm: Dividend = Quotient × Divisor + Remainder

1.
3x²+4x－7 = (x+2) × Divisor－3
3x²+4x－4 = (x+2) × Divisor
Divisor = (3x²+4x－4) / (x+2)

然後用Long division或者Synthetic division計 (3x²+4x－4) ÷ (x+2)

就會計到Divisor = 3x－2

難怪... 我solve左上面果part- -"" (x+?)(x-?) - -""

3) When a polynomial f(x) is divided by 2x^2-x+3, the quotient and the remainder are 8x-3 and 4 respectively. Find remainder when f(x) divided by 1-4x..

thx

First find f(x),
f(x)=(2x^2-x+3)(8x-3)+4=?
and then you can use remainder theorem, substitute x=1/4 into f(x)
then just use the calculator to find the answer.
The answer is the remainder