Tìm tập xác địh của các hàm sô sau :
a) y= \(\dfrac{x-1}{x+2}\)
b) y= \(\dfrac{x-1}{x2-3x-4}\)
c)y= \(\dfrac{2x}{x2+x+1}\)
d) y= \(\sqrt{2x-4}\)
e) y= \(\sqrt{5-6x}\)
f) y= \(\sqrt{\dfrac{x+1}{x-2}}\)
g) y= \(\sqrt{x-1}\) + \(\sqrt{3-x}\)
h) y=\(\dfrac{3}{\sqrt{x-5}}\)
i) y= \(\sqrt{x-1}\) + \(\sqrt{2x-1}\)
k) y= \(\sqrt{2-x}\) + \(\sqrt{3-x}\)
l) y= \(\dfrac{2}{\left|x\right|-3}\)
m) y= \(\dfrac{3x}{x-3}\)+ \(\sqrt{x+2}\)