Question 133467
In order to graph the tow function, just do them one at a time.
The {{{8^-x}}} is the same as {{{ 1/8^x }}}. So as x increases, that function gets smaller.

{{{f(x) = 2^(3x) }}} will grow as x increases. To find a reasonable scale, find the values for both functions at x = 0 and x = 1

g(0) = 1
g(1) = 1/8

f(0) = 1
f(1) = 8

{{{graph(300, 200, -10, 10, -10, 10, 2^(3x), 1/8^x ) }}}