Cho a/b=c/d cm rằng a)a/a-b=c/c-d
b) a/b=a+c/b+d
c) a/3a+b=c/3c+d
d)a.b/bd=a^2+c^2/b^2+d^2
E) a.b/c.d=a^2-b^2/c^2-d^2
F) a.b/c.d=(a-b)^2/(c-d)^2
Cho \(\frac{a}{b}=\frac{c}{d}\). Chứng minh: \(\frac{2.a^2-3.a.b+3.b^2}{2.b^2+3.a.b}=\frac{2.c^2-3.c.d+5.d^2}{2.d^2+3.c.d}\)
Cho a/b = c/d . CMR a^2 - b^2 / c^2 - d^2 = a.b / c.d
cho a/b = c/d
CMR
a, a^2-b^2/a.b = c^2-d^2/c.d
b, (a+b)^2/ a^2 + b^2= (c+d)^2/c^2+d^2
chung minh : neu a/b = c/d thi a^2.b^2/c^2.d^2 = a.b/c.d
B1:
Cho a/b = c/d CMR:
a) 2a + 3b/ 2a - 3b = 2c + 3d/ 2c - 3d
b)a.b/c.d = a^2 - b^2/ c^2 - d^2
c)(a +b / c+d)^2 = a^2 +b^2/c^2 + d^2
cho a/b=c/d chứng minh a.b/c.d=((a+b)^2/c+d)^2
cho a/b=c/d chứng minh:
a ) 5a+3b/5a-3b = 5c+3d
b) a^2+B^2/c^2+d^2=a.b/c.d
cho a/b = c/d . tính \(\frac{a.b}{c.d}+\left[\left(\frac{a+b}{c+d}\right)^2:\left(\frac{a^2+b^2}{c^2+d^2}\right)\right]-\frac{a^2-b^2}{c^2-d^2}\)
