PD

Cho các số a,b,c \(\ne0\) t/m \(b\ne c;a+b\ne c;c^2=2\left(ac+bc-ab\right)\)

CM: \(\frac{a^2+\left(a-c\right)^2}{b^2+\left(b-c^2\right)}=\frac{a-c}{b-c}\)