\(\frac{a}{b}=\frac{c}{d}\)
\(\left(2a+3b\right)\left(4c-5d\right)=\left(4a-5b\right)\left(2c+3d\right)\)
\(\Leftrightarrow8ac-10ad+12bc-15bd=8ac+12ad-10bc-15bd\)
\(\Leftrightarrow-10ad+12bc=12ad-10bc\)
\(\Leftrightarrow\left(-10ad+12bc\right)+\left(-12bc-12ad\right)=\left(12ad-10bc\right)+\left(-12bc-12ad\right)\)
\(\Leftrightarrow22bc=22ad\)
cho a/b = c/d chứng minh 2a-3b/4a+5b =2c-3d/4c+5d
Cho \(\dfrac{a}{b}=\dfrac{c}{d}\). Chứng minh:
1) \(\dfrac{2a+3c}{2b+3d}=\dfrac{2a-3c}{2b-3d}\)
2) \(\dfrac{4a-3b}{4c-3d}=\dfrac{4a+3b}{4c+3d}\)
3) \(\dfrac{3a+5b}{3a-5b}=\dfrac{3c+5d}{3c-5d}\)
4) \(\dfrac{3a-7b}{b}=\dfrac{3c-7d}{d}\)
cho tỉ lệ thức : a/b=c/d. Chứng minh
a) 3a+5b/3a-5b=3c+5d/3c-5d
b) 2a+3b/2a-3b=2c+2c-3d
( 2a + 3b) x ( 4c - 5d) = (4a - 5b) x (2c + 3d)
cho a/b=c/d CMR
a, a-b/a+b = c-d/c+d
b, 2a+3b/2c+3d = 4a-5b/4c-5d
AI GIÚP MIK VS Ạ
Cho tỉ lệ thức \(\frac{a}{b}=\frac{c}{d}\).CMR : \(\frac{2a+3b}{2c+3d}=\frac{4a-5b}{4c-5d}\)
Cho tỉ lệ thức a/b=c/d.Chứng minh
a)3a+5b/3a-5b=3c+5d/3c-5d
b) 2a + 3b/ 2a - 3b= 2c+3d/2c-3d
c)ab/cd=a^2-b^2/c^2-d^2
Cho \(\frac{a}{b}=\frac{c}{d}\)Chứng minh
a) (2a + 3b).(4c - 5d) = (4a - 5b) . (2c + 3d)
b) \(\frac{a^3+b^3}{c^3+d^3}=\frac{a^3-b^3}{c^3-d^3}\)
AI LÀ THẦN ĐỒNG THÌ VÀO ĐÂY LÀM NÀO
cho tỉ lệ thức \(\frac{a}{b}=\frac{c}{d}\).chứng minh
a)\(\frac{3a+5b}{3a-5b}=\frac{3c+5d}{3c-5d}\)
b) \(\frac{2a+3b}{2a-3b}\)=\(\frac{2c+3d}{2c-3d}\)
