2a+b=\(\frac{7ab}{6}=\frac{21a}{2b}\)
Tim\(\frac{a}{b}=\frac{c}{d}CMR\frac{a}{b}=\frac{c}{d}=\frac{2a-3c}{2b-3d}\)
\(Cho:\frac{2y+2z-x}{a}=\frac{2z+2x-y}{b}=\frac{2x+2y-z}{c};trongđó:a,b,c,2b+2c-a,2c+2a-b,2a+2b-c\ne0.cmr:\frac{x}{2b+2c-a}=\frac{y}{2c+2a-b}=\frac{z}{2a+2b-c}\)
Tim a,b,c biet \(\frac{a}{2}\)= b = \(\frac{c}{3}\)va a - 2b + c =210
a) tim a,b,c biet: \(\frac{a}{-2}\)=\(\frac{b}{3}\);\(\frac{b}{5}\)=\(\frac{c}{4}\)va a+2b+c=32
b) biet so do 3 goc cua mot tam giac ti le voi 4;6;8 tim so do moi goc cua tam giac do?
Cho \(\frac{2a+b}{c}=\frac{2b+c}{a}=\frac{2c+a}{b}.Tính: \frac{2a+b}{c}+\frac{a}{2b+c}+\frac{3b}{2c+a}\)
b1: cho\(\frac{a}{2b}\)=\(\frac{b}{2c}=\frac{c}{2d}=\frac{d}{2a}\)
tinhính A=\(\frac{2011a-2010b}{c+d}\)+ \(\frac{2011b-2010c}{a+b}\)+\(\frac{2011c-2010d}{a+b}\)+\(\frac{2011d+2010a}{b+c}\)
bai2 a, Tim (x,y) thuoc Z biet x+y+xy=2
b, tim Max Q=\(\frac{27-x}{12-x}\)(x thuoc Z)
CHO \(\frac{2a+b}{c}=\frac{2b+c}{a}=\frac{2c+a}{b}\)
TíNH.\(\frac{2a+b}{c}+\frac{a}{2b+c}+\frac{3b}{2c+a}\)
Tính gtrị bthức
\(A=\frac{2a-5b}{a-3b}\)với\(\frac{a}{b}=\frac{6}{8}\)
\(B=\frac{3a-b}{2a+7}+\frac{3b-a}{2b-7}\)với a-b=7
