(a+b).(c-2d)=(a-2b).(c+d)
ac-2ad+bc-2bd=ac+ad-2bc-2bd
ac-ac+bc+2bc=2ad+ad+2bd-2bd
3bc=3ad
bc=ad
=> a/b=c/d
(a+b).(c-2d)=(a-2b).(c+d)
ac-2ad+bc-2bd=ac+ad-2bc-2bd
ac-ac+bc+2bc=2ad+ad+2bd-2bd
3bc=3ad
bc=ad
=> a/b=c/d
Cho \(\frac{a+2c}{b+2d}=\frac{2a+c}{2b+d}\) .
CMR : \(\frac{a}{b}=\frac{a+c}{b+d};\frac{2a-c}{2b-d}=\frac{a-2c}{b-2d};\frac{a+2b}{a-b}=\frac{c+2d}{c-d}\)
Cho:\(\frac{a}{b}=\frac{b}{c}=\frac{c}{d}=\frac{d}{a}\)
Tính: P\(\frac{2a-b}{2c-d}+\frac{2b-c}{2d-a}+\frac{2c-d}{2a-b}+\frac{2d-a}{2b-c}\)
Giúp với ai nhanh mình tick cho.
Cho \(\frac{a}{b}=\frac{c}{d}\) CMR: \(\frac{4a-2b}{5a+2b}=\frac{4c-2d}{5c+2d}\)
Cho a,b,c,d là các số thực thỏa mãn : \(\frac{2a+b+c+d}{a}=\frac{a+2b+c+d}{b}=\frac{a+b+2c+d}{c}=\frac{a+b+c+2d}{d}\)+2d
Tính M =\(\frac{a+b}{c+d}+\frac{b+c}{d+a}+\frac{c+d}{a+b}+\frac{d+a}{b+c}\)
\(Cho\) \(\frac{a}{b}=\frac{c}{d}\)
\(CMR:\)\(a,\frac{5a-3b}{3a+2b}=\frac{5c-3d}{3c+2d}\)
\(b,\frac{2a+b}{a-2b}=\frac{2c+d}{c-2d}\)
Cho \(\frac{a+b}{c+d}\)=\(\frac{a-2b}{c-2d}\)(a,b,c khác 0)
CMR \(\frac{a}{b}\)=\(\frac{c}{d}\)
Cho \(\frac{a}{b}=\frac{c}{d}\).CMR :
a/ \(\frac{a+c}{b+d}=\frac{a-c}{b-d}\)
b/\(\frac{2a+3c}{2d+3d}=\frac{2a-3c}{2b-3d}\)
c/\(\frac{a^2+c^2}{b^2+d^2}=\frac{ac^2}{bd}\)
a) Cho \(\frac{a+b}{b}\)=\(\frac{c+d}{d}\).CMR \(\frac{a}{b}\)=\(\frac{c}{d}\)
b) Cho \(\frac{a}{a-2b}\)=\(\frac{c}{c-2d}\).CMR \(\frac{a}{b}\)=\(\frac{c}{d}\)
Cho: \(\frac{2a+b+c+d}{a}=\frac{a+2b+c+d}{b}=\frac{a+b+2c+d}{c}=\frac{a+b+c+2d}{d}\)
Tính M= \(\frac{a+b}{c+d}=\frac{b+c}{d+a}=\frac{c+d}{a+b}=\frac{d+a}{b+c}\)