# Math Help - help graphing 3 functions

1. ## help graphing 3 functions

Graph these functions.

$f(x)=3^{x}$

$f(x)=-3(3)^{x}$

$f(x)=20\left(\frac{1}{4}\right)^{x}$

I know graphs don't have to be perfect. But how would these look....if there was a table for each function with x values of -3, -2,-1, 0, 1, 2, 3 ?

The tables, respectively, would be:

x/ f(x)
-3/ (1/27)
-2/ (1/9)
-1/ (1/3)
0/ 1
1/ 3
2/ 9
3/ 27

x/ f(x)
-3/ (-1/9)
-2/ (-1/3)
-1/ -1
0/ -3
1/ -9
2/ -27
3/ -81

x/ f(x)
-3/ 1280
-2/ 320
-1/ 80
0/ 20
1/ 5
2/ (5/4)
3/ (5/16)

2. do you know the graph of $e^x$?
if does, then the graph of $a^x$ for $a>1$ looks like the graph of $e^x$.. (see graph1)
if you multiply a negative number from that $a^x$ for $a>1$, the graph is reflected about the x-axis.. (see graph2)

however, the graph of $a^x$ for $0 is a reflection about the y-axis.. (see graph3 and graph4)