Question

giải các phương trình chứa ẩn

a) \(\dfrac{2\cdot\left(x^2+x+6\right)}{x^3-8}+\dfrac{2}{2-x}=\dfrac{3}{x^2+2x+4}\)

b) \(\dfrac{6}{x^3+1}-\dfrac{1-x}{x^2-x+1}=\dfrac{5}{x+1}\)

c) \(\dfrac{1}{x^2+3x+2}-\dfrac{3}{x^2-x-2}=\dfrac{-1}{x^2-4}\)

Answer 1

Vậy x = 0 hoặc x = 5/4

(ĐK: x² - x khác -1)

Answer 2

c: \(\Leftrightarrow\dfrac{1}{\left(x+2\right)\left(x+1\right)}-\dfrac{3}{\left(x-2\right)\left(x+1\right)}=\dfrac{-1}{\left(x-2\right)\left(x+2\right)}\)

\(\Leftrightarrow x-2-3x-6=-x-1\)

=>-2x-4=-x-1

=>2x+4=x+1

=>x=-3(nhận)