Question

Quy đồng  1/(a - b)(b - c); 1/(c - b)(c - a); 1/(b - a)(a - c)

Answer 1

\(\dfrac{1}{\left(a-b\right)\left(b-c\right)}=\dfrac{a-c}{\left(a-b\right)\left(b-c\right)\left(a-c\right)}\)

\(\dfrac{1}{\left(c-b\right)\left(c-a\right)}=\dfrac{1}{\left(a-c\right)\left(b-c\right)}=\dfrac{a-b}{\left(a-c\right)\left(b-c\right)\left(a-b\right)}\)

\(\dfrac{1}{\left(b-a\right)\left(a-c\right)}=\dfrac{-1}{\left(a-b\right)\left(a-c\right)}=\dfrac{-b+c}{\left(b-c\right)\left(a-b\right)\left(a-c\right)}\)