Bài 5:
a) Ta có:
\(\dfrac{1}{x-a}=\dfrac{x-b}{\left(x-a\right)\left(x-b\right)}\)
\(\dfrac{1}{x-b}=\dfrac{x-a}{\left(x-a\right)\left(x-b\right)}\)
Mà MSC là: \(x^2-5x+6=x^2-2x-3x+6=\left(x^2-2x\right)-\left(3x-6\right)\)
\(=x\left(x-2\right)-3\left(x-2\right)=\left(x-2\right)\left(x-3\right)\)
\(\Rightarrow\left(x-a\right)\left(x-b\right)=\left(x-2\right)\left(x-3\right)\)
Vậy \(a=2,b=3\)
b) Hai phân thức đó là:
\(\dfrac{1}{x-2}=\dfrac{x-3}{\left(x-2\right)\left(x-3\right)}\)
\(\dfrac{2}{x-3}=\dfrac{2\left(x-2\right)}{\left(x-3\right)\left(x-2\right)}=\dfrac{2x-4}{\left(x-2\right)\left(x-3\right)}\)
Đúng 2
Bình luận (1)
