Violympic toán 7
Các câu hỏi tương tự
cho a^2+b^2/c^2+d^2=ab/cd cmr a/b=c/d hoặc a/b = d/c
Cho a/b=c/d .Cmr :ab/cd = (a+b)^2/(c+d)^2 .
biết:\(\dfrac{a^2+b^2}{c^2+d^2}=\dfrac{ab}{cd}\) với a,b,c,d\(\ne\)0. CMR:
\(\dfrac{a}{b}=\dfrac{c}{d}\) hoặc \(\dfrac{a}{b}=\dfrac{d}{c}\)
Cho \(\dfrac{a}{b}=\dfrac{c}{d}.CMR:\)
a, \(\dfrac{a^2-b^2}{ab}=\dfrac{c^2-d^2}{cd}\)
b, \(\dfrac{\left(a+b\right)^2}{a^2+b^2}=\dfrac{\left(c+d\right)^2}{c^2+d^2}\)
Cho tỉ lệ thức \(\dfrac{a}{b}=\dfrac{c}{d}.CMR:\dfrac{ab}{cd}=\dfrac{a^2-b^2}{c^2-d^2}\)
cho a/b = c/d, cmr: \(\dfrac{ab}{cd}=\dfrac{\left(a-b\right)^2}{\left(c-d\right)^2}\)
Cho \(\frac{a^2+b^2}{c^2+d^2}=\frac{ab}{cd}\)
CMR \(\left[{}\begin{matrix}\frac{a}{b}=\frac{c}{d}\\\frac{a}{b}=\frac{d}{c}\end{matrix}\right.\)
Cho \(\dfrac{a}{b}< \dfrac{c}{d}\)và b, d > 0 . CMR : \(\dfrac{a}{b}< \dfrac{ab+cd}{b^2+d^2}< \dfrac{c}{d}\)
cho tỉ lệ thức \(\frac{a}{b}=\frac{c}{d}\)
cmr \(\frac{ab}{cd}=\frac{a^2-b^2}{c^2-d^2}\)