How do you sketch the graph of y=log_2(x+2)?

2 Answers
Nov 29, 2016

The graph of y is the standard graph of lnx transformed 2 units left and scaled by 1/ln2

Explanation:

To change the base of the log to base e:

log_2 x = ln(x)/ln2

In this example y=log_2(x+2)

:. y= ln(x+2)/ln2

The graph of y is the standard graph of lnx transformed 2 units left and scaled by 1/ln2

y is defined for x> -2
y has a single zero at x=-1
y=1 at x=0

The graph of y is shown below

graph{ln(x+2)/ln2 [-10, 10, -5, 5]}

Nov 29, 2016

x-intercept is -1; y-intercept is 1.
As x to-2, y to -oo; as x to oo, y to oo. Graph for the inverse x=2^y-1 is inserted.

Explanation:

Cuts axes at (-1, 0) and (0, 1). x = -2 is the asymptote.

For graphing, I have used the inverse x = 2^y-1.

graph{2^y-x-2=0 [-10, 10, -5, 5]}