Given the following functions:
f(x) = 2x - 1
g(x) = 3x
h(x) = x2 + 1
f(g(x)) means that we will be substituting the function of g(x) as x of the f(x) function.
We get,
[tex]f\mleft(g\mleft(x\mright)\mright)\text{ }\rightarrow\text{ f(x) = 2x - 1 }\rightarrow\text{ }f(g(x))=\text{ 2(3x) - 1}[/tex][tex]f(g(x))=\text{ 6x - 1}[/tex]