How do you find the limit of a logarithmic function?

Question

The function is: y=14.873ln(x) - 2.9361

Answer 1

Dear Isabel,

      You can enter values for X in a table to find values of Y.  However, the easiest thing to do is use a graphing calculator.  Just enter the equation for y in the graphing mode, just like you gave it.  Then press graph.  You may want to adjust the graph, so that you can see more of the picture.  Go to the WINDOW function.  Here are some values that might make it easier to see, so that you can find the limit:

X-min =0     X-max=10, Y-min=-50, Y-max=100 

     Next, go to the Graph TABLE (2nd GRAPH).  Notice that the last point that makes sense is at (1, -2.936).  After that point, as X is approaching zero, you will read an error.  Also, the graph doesn't have any negative x values. The y values keep moving downward, but the x values never approach zero.  This graphing is moving downward in a negative direction and never approaching zero.  This would be a negative infinity.  Also,  look at what the graph is doing on the positive side; as X increases, Y increases, so the graph is moving towards a positive infinity towards the right.

 

If I have helped you, please give me a thumbs up.

                                            Susan C.