Question 150291
How do you graph f(x)= log 3x?
:
y = f(x)
then
y = log(3x)
:
WE can't have log of zero or a neg number therefore all values: x > 0
:
Start with x = .22, using a calc, enter log(3*.2) = -.22
x = .6; log(3*.6) = +.25 
x = 1; log(3*1) = +.48
x = 1.4 log(3*1.4) = +.62
:
After this the curve flattens out so we can jump to x = 2
x = 2 log(3*2) = .78
x = 4 log(3*4) = 1.08
Continuing like this make a table
 x | y
-------
.2 |-.22
.6 |+.26
1.0|+.48
1.4|+.62
2.0|+.78
4.0|1.08
6.0|1.26
:
Plot this on graph, scaled about like this: 
{{{ graph( 300, 200, -1, 8, -2, 3, log(3x) ) }}}
:
:
Did this make sense to you?