...again.

1. lim sec x - 1 / xsecx (x--->0)

2. lim (1-cosx)^2 / x (x--->0)

3. lim 5x / sin 4x (x--->0)

Sometimes I get these, and sometimes I don't. Is there any specific way I'm supposed to look at these trig. functions? I keep getting marked off for the way I've been solving them. =/

Any help is greatly appreciated!