How do you graph #f(x) = log_2x-1#?

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Answer 1 · 2016-08-05T16:30:34

Use the inverse relation #x=2(2^f)#.Plot points for #(x, 2(2^f)), f = ...,+-4, +-3, +-2, +-1, 0# and make the graph.# x>0#, to make #log_2x# real.

#x>0#, to make #log_2x# real.

#log_2x=f+1#

Inversely,

#x=2^(f+1)=2(2^f)#

Make a graph through the plots

#(x, f)=(2(2^f), f): ...(1/8, -4) (1/4, -3) (1/2, -2)#

# (1, -1) (2, 0) (4, 1) (8, 2) 16, 3) (32, 4) ...#.

As #x to 0, f to -oo#.

So, the graph has the vertical asymptote as f-axis, in the negative

direction.