Cho a , b ,c ,d thỏa mãn : \(\frac{a}{a+2b}=\frac{c}{c+2d}\). Tính \(\frac{a^2d^2-4b^2c^2}{abcd}\)
Cho a ,b ,c , d thỏa mãn : \(\frac{2a+3c}{2b+3d}=\frac{3a-4c}{3b-4d}\).. Tính \(\frac{4a^3d^3-b^3c^3}{4b^3c^3-a^3d^3}\)
Cho \(\frac{a}{b}=\frac{c}{d}\).CMR: \(\frac{a+2c}{b+2d}=\frac{a-3c}{b-3d}\)
Chứng minh răngnếu \(\frac{a}{b}=\frac{c}{d}thiA:\frac{a^2+2c^2}{b^2+2d^2}=\left(\frac{a+3c}{b+3d}\right)^2\)
Cho \(\frac{a}{b}=\frac{c}{d}\)
a) Chứng minh \(\frac{3a+2c}{3d+2d}=\frac{3c-5a}{3d-5b}\)
b) Chứng minh \(\frac{a^2}{b^2}=\frac{2c^2-ac}{2d^2-bd}\)
A)\(CMR:\frac{a+2c}{b+2d}\)\(=\frac{3a+c}{3b+d}\)
B)\(CMR:\frac{a-c}{a+3c}=\frac{b-d}{b+3d}\)
A)\(CMR:\frac{a+2c}{b+2d}\)\(=\frac{3a+c}{3b+d}\)
B)\(CMR:\frac{a-c}{a+3c}=\frac{b-d}{b+3d}\)
A)\(CMR:\frac{a+2c}{b+2d}\)\(=\frac{3a+c}{3b+d}\)
B)\(CMR:\frac{a-c}{a+3c}=\frac{b-d}{b+3d}\)
Cho \(\frac{a}{b}=\frac{b}{c}=\frac{c}{d}=\frac{d}{a}\) \(\left(a,b,c,d\ne0;a+b+c+d\ne0\right)\)
Tính: \(M=\frac{3a-2b}{c+d}+\frac{3b-2c}{d+a}+\frac{3c-2d}{a+b}+\frac{3d-2a}{b+c}\)
Cho các số thực a,b,c,d khác 0 thỏa mãn \(\frac{a}{b}=\frac{b}{c}=\frac{c}{d}.\)Chứng minh rằng
\(\frac{a^3+2b^3+3c^3}{b^3+2c^3+3d^3}=\left(\frac{a+2b+3c}{b+2c+3d}\right)^3=\frac{a}{d}\)