Question

Chứng minh: \(\dfrac{1}{a\left(a+2\right)}=\dfrac{1}{2}\left(\dfrac{1}{a}-\dfrac{1}{a+2}\right)\)

Answer 1

\(VP=\dfrac{1}{2}\cdot\dfrac{a+2-a}{a\left(a+2\right)}=\dfrac{2}{2a\left(a+2\right)}=\dfrac{1}{a\left(a+2\right)}=VT\)

Answer 2