CÓ a/b = C/d = K suy ra a = b *k, C = k 3a + 2b /b = 3*b*k + 2*b*k / b*k = B * ( 3k + 2k ) / b * k = 3k + 2k/ k. 3c + 2d / k = 3d *k + 2b * k / d*k = d * ( 3k + 2k ) / d*k = 3k + 2k / k. Bạn ơi mk làm ko bt là đúng ko nha
Cho tỉ lệ thức \(\dfrac{a}{b}=\dfrac{c}{d}\). Chứng minh rằng
a) \(\dfrac{a}{b}=\dfrac{c}{d}=\dfrac{a+4c}{b+4d}\)
b) \(\dfrac{a}{b}=\dfrac{c}{d}=\dfrac{3a+2c}{3b+2d}\)
c) \(\dfrac{a}{c}=\dfrac{b}{d}=\dfrac{a-2b}{c-2d}\)
d) \(\dfrac{a}{c}=\dfrac{b}{d}=\dfrac{5a-2b}{5c-2d}\)
tính M=3A-2B/C+D + 3B-2C/D+A + 3C-2D/A-B + 3D-2A/B+C
AI GIẢI CHI TIẾT BÀI NÀY GIÙM MÌNH VỚI
Cho \(\frac{a}{b}=\frac{c}{d}\)
Chứng minh
a, \(\frac{a}{b}=\frac{c}{d}=\frac{3a-3c}{5b-5d}=\frac{2b-3c}{2b-3d}\)
b, \(\frac{a+b}{c+a}=\frac{a-b}{c-d}\)
1 Chứng tỏ rằng :
a) 0,(43) + 0,(56) = 1
b) 0,(333) . 3 = 1
2. Cho \(\dfrac{a}{b}=\dfrac{c}{d}\) Chứng minh \(\dfrac{a}{3a+b}=\dfrac{c}{3c+d}\)
3. Tìm a,b,c
\(\dfrac{a}{2}=\dfrac{b}{3}=\dfrac{c}{4}\) và a + 2b - 3c = -20
cho a/b=c/d . chứng minh rằng 2a+3c / ạ= 2b+3d/b
Cho a+b+c+d khác 0 sao cho: \(\dfrac{b+c+d}{a}=\dfrac{a+c+d}{b}=\dfrac{b+a+d}{c}=\dfrac{c+b+a}{d}\)
Hãy tính: M = \(\dfrac{2a+5b}{3c+4d}-\dfrac{2b+5c}{3d+4a}-\dfrac{2c+5d}{3a+4b}+\dfrac{2d+5a}{3c+4b}\)
Cho tỉ lệ thức: a/b = c/d. CM:
a, a/b=c/d=a+4c/b+4d
b, a/b=c/d=3a+2c/3b+2d
c, a/c=b/d=a-2b/c-2d
d, a/c=b/d=5a-2b/5x-2d
Giúp mk vs. Năn nit đóa. Mk sẽ tick choa.
Cho \(\dfrac{a}{b}=\dfrac{c}{d}\) . Chứng minh :
a, \(\dfrac{a^3+b^3}{c^3+d^3} = \dfrac{a^3-b^3}{c^3-d^3}\)
b, \(\dfrac{(a+b)^3}{(c+d)^3}=\dfrac{a^3+b^3}{c^3+d^3}\)
c, \(\dfrac{(a-b)^3}{(c-d)^3}=\dfrac{3a^2+2b^2}{3c^2+2d^2}\)
d, \(\dfrac{4a^4+5b^4}{4c^4+5d^4}=\dfrac{a^2b^2}{c^2d^2}\)
e, \(\dfrac{a^{10}+b^{10}}{(a+b)^{10}} = \dfrac{c^{10}+d^{10}}{(c+d)^{10}}\)
cho \(\frac{a}{b}=\frac{c}{d}\left(b,c,d\ne0;c-2d\ne0\right)\)
chứng minh rằng \(\frac{\left(a-2b^4\right)}{\left(c-2d^4\right)}=\frac{a^4+2017b^4}{c^4+2017d^a}\)
