Given that lim x->c f(x)=6 and that lim x->c g(x)= -4, evaluate the following limit. Assume that c is a constant. The x in front of the f is confusing me.

Question

lim [xf(x) + 3 g(x)]^2
x->c

Answer 1

The x in front of the f is any constant you would put in the equation.

Example: x->5 5=c
lim [xf(x) + 3 g(x)]^2
x->5

so, [5*6 + 5*(-4)]^2

You should be able to do the rest.

Answer 2

[c*6 + 3*(-4)]^2 = (6c -12)^2
= 36c^2 - 144c + 144