Question

determine whether f(x) approaches ∞ or −∞ as x approaches −6 from the left and from the right.
f(x) = (sec πx)/4
lim
x→−6− =(sec πx)/4

lim
x→−6+ = (sec πx)/4

please help, don't understand..i know i have to plug in -6, but how do i determine?