Cho \(\dfrac{a}{b}\)=\(\dfrac{c}{d}\) chứng minh rằng:
a) \(\dfrac{a}{a-b}\)=\(\dfrac{c}{c-d}\)
b) \(\dfrac{a}{b}\)=\(\dfrac{a+c}{b+d}\)
c)\(\dfrac{a}{3a+b}\)=\(\dfrac{c}{3c+b}\)
d) \(\dfrac{a.c}{b.c}\)=\(\dfrac{a^2+c^2}{b^2+d^2}\)
e) \(\dfrac{a.b}{c.d}\)=\(\dfrac{a^2-b^2}{c^2-d^2}\)
f) \(\dfrac{a.b}{c.d}\)=\(\dfrac{\left(a-b\right)^2}{\left(c-d\right)^2}\)
Loga
Toán lớp 7
