đặt a/b=c/d=k=>a=bk;c=dk rồi thay vào mà tính
đặt a/b=c/d=k=>a=bk;c=dk rồi thay vào mà tính
Cho \(\frac{a}{b}\)=\(\frac{c}{d}\)chứng minh rằng
a)\(\frac{a}{a-b}\)=\(\frac{c}{c-d}\)
b)\(\frac{a}{b}=\frac{a+c}{b+d}\)
c)\(\frac{a}{3a+b}=\frac{c}{3c+d}\)
d)\(\frac{a.c}{b.d}=\frac{a^2+c^2}{b^2+d^2}\)
f)\(\frac{a.b}{c.d}=\frac{\left(a-b\right)^2}{\left(c-d\right)^2}\)
Cho \(\frac{a}{b}=\frac{c}{d}\)CMR:
\(a,\frac{a.c}{b.d}=\frac{a^2+c^2}{b^2+d^2}\) \(b,\frac{a.c}{b.d}=\frac{a^2-c^2}{b^2-d^2}\)\(c,\frac{a.c}{b.d}=\frac{\left(a-b\right)^2}{\left(c-d\right)^2}\)
GIẢI GIÚP TỚ NHANH NHÉ! CẢM ƠN NHIỀU!
cho \(\frac{a}{b}\)= \(\frac{c}{d}\)chứng minh rằng:
a) \(\frac{a}{3a+b}=\frac{c}{3c+d}\)
b)\(\frac{a.c}{b.d}=\frac{a^2+c^2}{b^2+d^2}\)
c) \(\frac{a.b}{c.d}=\frac{a^2-b^2}{c^2-d^2}\)
1. Chứng minh tỉ lệ thức:
Cho \(\frac{a}{b}=\frac{c}{d}\) , chứng minh rằng :
a, \(\frac{a}{3a+b}\) \(=\frac{c}{3c+d}\)
b, \(\frac{a.c}{b.d}=\frac{a^2+c^2}{b^2+d^2}\)
c, \(\frac{a.b}{c.d}=\frac{a^2-b^2}{c^2-d^2}\)
Chứng minh rằng \(\frac{a}{b}=\frac{c}{d}\) biết:
a) \(\frac{a}{a-b}=\frac{c}{c-d}\) b)\(\frac{a.c}{b.d}=\frac{a^2+c^2}{b^2+d^2}\)
c) \(\frac{a.b}{c.d}=\frac{a^2-b^2}{c^2-d^2}\)
cho \(\frac{a}{b}=\frac{c}{d}.CMR\frac{a.c}{b.d}=\frac{a^2+c^2}{b^2+d^2}\)
cho \(\frac{a}{b}=\frac{c}{d},\)(b+d khác 0), CMR\(\frac{a^2+c^2}{b^2+d^2}=\frac{a.c}{b.d}\)
Cho \(\frac{a}{b}=\frac{c}{d}\). CMR \(\frac{a.c}{b.d}=\frac{a^2+c^2}{b^2+d^2}\)
Cho \(\frac{a}{b}=\frac{c}{d}\)với a,b,c,d khác 0
C/m \(\frac{a.c}{b.d}=\frac{a^2+c^2}{b^2+d^2}\)