1. tìm x, ya, x - y +2xy =7b, xy + 3x -y = 6c, \(\frac{1}{x}\)+ \(\frac{1}{y}\)=\(\frac{1}{5}\)d, (6 \(\sqrt{x-1}\)) \(⋮\)( 2\(\sqrt{x-3}\))4. tìm x \(\in\)za, A =\(\frac{1-2x}{x+3}\)\(\in\)zb, B = \(\frac{2012\sqrt{x+5}}{1006\sqrt{x+1}}\)\(\in\)zHELP ME...
Đọc tiếp
1. tìm x, y
a, x - y +2xy =7
b, xy + 3x -y = 6
c, \(\frac{1}{x}\)+ \(\frac{1}{y}\)=\(\frac{1}{5}\)
d, (6 \(\sqrt{x-1}\)) \(⋮\)( 2\(\sqrt{x-3}\))
4. tìm x \(\in\)z
a, A =\(\frac{1-2x}{x+3}\)\(\in\)z
b, B = \(\frac{2012\sqrt{x+5}}{1006\sqrt{x+1}}\)\(\in\)z
HELP ME ........!!!!!!!!!
