\(cho\)cho:\(\dfrac{a}{b}=\dfrac{b}{c}=\dfrac{c}{d}.\) cmr: \(\left(\dfrac{a+b+c}{b+c+d}\right)^3=\dfrac{a}{d}\)
Cho \(\dfrac{a}{b}=\dfrac{b}{c}=\dfrac{c}{d}\) CMR :\(\left(\dfrac{a+b+c}{b+c+d}\right)^3=\dfrac{a}{d}\)
Cho \(\dfrac{a}{c}=\dfrac{c}{b}=\dfrac{b}{d}\)
CMR:\(\dfrac{a^3+c^3-b^3}{c^3+b^3-d^3}=\dfrac{a}{d}\)
CMR: Tu \(\dfrac{a}{b}=\dfrac{c}{d}+1\)
ta co the suy ra :\(\dfrac{a-b}{a+b}=\dfrac{c-d}{c+d}\)
CMR:\(\dfrac{a+b}{b+c}=\dfrac{c+d}{d+a}\)thì a=c hoặc a+b+c+d =0
CMR: nếu \(\dfrac{a}{b}\)=\(\dfrac{c}{d}\) khác 1 thì \(\dfrac{a+b}{a-b}\)=\(\dfrac{c+d}{c-d}\)với a,b,c,d khác 0
CMR: nếu a\(^2\)=bc thì \(\dfrac{a+b}{a-b}\)= \(\dfrac{c+a}{c-a}\)điều dảo lại có đúng hay ko
giúp mk nha các bn
Cho các số a, b, c, d thõa mản điều kiện:
\(\dfrac{a}{3b}=\dfrac{b}{3c}=\dfrac{c}{3d}=\dfrac{d}{3a}\) và \(a+b+c+d\ne0\)
CMR: a = b = c = d
Cho tỉ lệ thức \(\dfrac{a}{b}=\dfrac{c}{d}\). CMR : \(\dfrac{ab}{cd}=\dfrac{a^2-b^2}{c^2-d^2}\) và \(\left(\dfrac{a+b}{c+d}\right)^2=\dfrac{a^2+b^2}{c^2+d^2}\)
Cho \(\dfrac{a}{b}=\dfrac{c}{d}\). CMR \(\dfrac{a}{2a+c}=\dfrac{b}{2b+d}\)