Hoàn thành .... sau đó tìm R(x) trong mỗi trường hợp:
a,R ( x ).(2x\(^2\))=\(\dfrac{3}{4}\)x\(^3\)
b,(-\(\dfrac{1}{3}\)x).R(x)=2x\(^2\)
c,R(x): ( 3x) = \(\dfrac{1}{3}\)x\(^3\)
d,4x\(^4\):R(x)=\(\dfrac{2}{3}\)x\(^2\)
e,R(x).(2x + 1)=4x\(^2\) + 4x + 1
f,(x\(^3\) + 3x\(^2\) - x - 3) : R (x) = x\(^2\) -1
giúp mình với ạ mình cảm ơn
a: \(R\left(x\right)\cdot2x^2=\dfrac{3}{4}x^3\)
=>\(R\left(x\right)=\dfrac{3}{4}x^3:2x^2=\dfrac{3}{8}x\)
b: \(\left(-\dfrac{1}{3}x\right)\cdot R\left(x\right)=2x^2\)
=>\(R\left(x\right)=2x^2:\left(-\dfrac{1}{3}x\right)=\left(2:\dfrac{-1}{3}\right)\left(x^2:x\right)=-6x\)
c: \(R\left(x\right):3x=\dfrac{1}{3}x^3\)
=>\(R\left(x\right)=\dfrac{1}{3}x^3\cdot3x=\dfrac{1}{3}\cdot3\cdot x^3\cdot x=x^4\)
d: \(4x^4:R\left(x\right)=\dfrac{2}{3}x^2\)
=>\(R\left(x\right)=4x^4:\dfrac{2}{3}x^2=\left(4:\dfrac{2}{3}\right)\left(x^4:x^2\right)=6x^2\)
e: \(R\left(x\right)\left(2x+1\right)=4x^2+4x+1\)
=>\(R\left(x\right)\cdot\left(2x+1\right)=\left(2x+1\right)^2\)
=>R(x)=2x+1
f: \(\left(x^3+3x^2-x-3\right):R\left(x\right)=x^2-1\)
=>\(R\left(x\right)=\dfrac{x^3-x+3x^2-3}{x^2-1}\)
=>\(R\left(x\right)=\dfrac{x\left(x^2-1\right)+3\left(x^2-1\right)}{x^2-1}=x+3\)
