chi a,,b,c thoa man (a+2b)(2b+3c)(3c+a)khac 0 va
\(\frac{a^2}{a+2b}+\frac{4b^2}{2b+3c}+\frac{9c^2}{3c+a}=\frac{a^2}{2b+3c}+\frac{4b^2}{a+3c}+\frac{9c^2}{a+2b}\)
cmr;\(\frac{a}{6}=\frac{b}{3}=\frac{c}{2}\)
cho a;b;c;x;y;z khác 0 thỏa mãn:
\(\frac{x^2-6xy}{a}=\frac{4y^2-3xz}{2b}=\frac{9z^2-2xy}{3c}\)
CMR:
\(\frac{a^2-6bc}{x}=\frac{4b^2-3ac}{2y}=\frac{9c^2-2ab}{3z}\)
cho a;b;c;x;y;z khác 0 thỏa mãn:
\(\frac{x^2-6xy}{a}=\frac{4y^2-3xz}{2b}=\frac{9z^2-2xy}{3c}\)
CMR:
\(\frac{a^2-6bc}{x}=\frac{4b^2-3ac}{2y}=\frac{9c^2-2ab}{3z}\)
cho a/b = c/d chung minh
1, ( 2a + 3c ) . ( 2b - 3d ) = ( 2a - 3c ) . ( 2b + 3d )
2, ( 4a + 3b ) . ( 4c - 3d ) = ( 4a - 3c ) . ( 4c + 3d )
cho a,b,c la 3 so thuc doi mot khac nhau va khac khong, thoa man: a+1/b=b+1/c=c+1/a. hay chung minh rang abc=1 hoac abc=-1
Cho 4 số thực a, b, c, d khác 0 thỏa mãn a+2b+3c+4d khác 0 và 3a+2b +3c+4d/a=a+6b+3c+4d/2b=a+2b+9c+4d/3c=a+2b+3c+12d/4a
Question Expandand simplify: 1. 8(x+5)-3(2x+7)
2. a(2b+c)+b(3c-2a)
3. 2y(y+5x)+x(3x+4y)
answer , 1. 8(x+5)-3(2x+7)=8x+40-6x+21=2x+61
2. a(2b+c)+b(3c-2a)=2ab+ac+3bc-2ab=ac+3bc=3abc^(2)
3. 2y(y+5x)+x(3x+4y)=2y^(2)+10xy+9x^(2)+4xy=9x^(2)+2y^(2)+14xy
a Explain what he has done wrong.
b work out the correct answer
\(\frac{a}{2b}\)=\(\frac{2b-2015c}{2c}\)=\(\frac{2016c-b}{2a}\)(a;b;c khac o)va a+b+c khac 0 chung minh a=b
Cho cac so a,b khac nhau va thoa man \(a+\frac{1}{a}=b+\frac{1}{b}\) Chung minh ab=1
