Math Is Fun Forum

Hannibal lecter

Member

Registered: 2016-02-11

Posts: 392

Shifting a function

In math whatever we plug number to x it shift it horizontally but if plug it like that f(x) +1 it shifted it vertically
But my problem in e^x it shifted on y-axis when I plug 1 for example. what is the secret behind that
Like e^(x+1)
It should shift the e^(x+1) to the left! But it’s didn’t happen why
Like x^2 when plug +1 which became (x+1)^2 it shifted it to left! Correct

Last edited by Hannibal lecter (2022-02-01 10:00:48)

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Wisdom is a tree which grows in the heart and fruits on the tongue

Bob

Administrator

Registered: 2010-06-20

Posts: 10,621

Re: Shifting a function

hi

I've just tried y = e^(x+1) in this function grapher:

https://www.mathsisfun.com/data/function-grapher.php

and the graph is e^x but moved one step left exactly as you expected.  For example the usual y intercept (0,1) has moved to (-1,1)

So why didn't this happen for you?  How did you plot the graph?

Bob

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Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

Hannibal lecter

Member

Registered: 2016-02-11

Posts: 392

Re: Shifting a function

oh sorry you are right I got a mistake
I saw it goes up a little so I thought it didn't moved to the left sorry now everything is clear I use a grapher not by hand
do you advice me to plot things on paper or keep using grapher computer?

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Wisdom is a tree which grows in the heart and fruits on the tongue

Bob

Administrator

Registered: 2010-06-20

Posts: 10,621

Re: Shifting a function

Oh good.  I'm glad you've got it sorted.

The grapher is great for a quick check and for comparing similar functions but it's also advisable to make sure you can plot and sketch curves as well.

For a plot you fix some x values and work the y values and then plot the points.

For a sketch you can do any or all of the following:

Find the y axis and x axis intercepts by putting x= 0 and y =o.

Consider how the function behaves as x tends to infinity and to minus infinity.

Are there any other obvious asymptotes?

Differentiate and investigate the zeros of the gradient function and hence identify maxima, minima, and points of inflexion.

Bob

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Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob