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Given a tabular function, create a new row to represent a vertical shift.

  1. Identify the output row or column.
  2. Determine the magnitude of the shift.
  3. Add the shift to the value in each output cell. Add a positive value for up or a negative value for down.

Shifting a tabular function vertically

A function f ( x ) is given in [link] . Create a table for the function g ( x ) = f ( x ) 3.

x 2 4 6 8
f ( x ) 1 3 7 11

The formula g ( x ) = f ( x ) 3 tells us that we can find the output values of g by subtracting 3 from the output values of f . For example:

f ( 2 ) = 1 Given g ( x ) = f ( x ) 3 Given transformation g ( 2 ) = f ( 2 ) 3 = 1 3 = 2

Subtracting 3 from each f ( x ) value, we can complete a table of values for g ( x ) as shown in [link] .

x 2 4 6 8
f ( x ) 1 3 7 11
g ( x ) −2 0 4 8
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The function h ( t ) = 4.9 t 2 + 30 t gives the height h of a ball (in meters) thrown upward from the ground after t seconds. Suppose the ball was instead thrown from the top of a 10-m building. Relate this new height function b ( t ) to h ( t ) , and then find a formula for b ( t ) .

b ( t ) = h ( t ) + 10 = 4.9 t 2 + 30 t + 10
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Identifying horizontal shifts

We just saw that the vertical shift is a change to the output, or outside, of the function. We will now look at how changes to input, on the inside of the function, change its graph and meaning. A shift to the input results in a movement of the graph of the function left or right in what is known as a horizontal shift , shown in [link] .

Figure_01_05_004
Horizontal shift of the function f ( x ) = x 3 . Note that h = + 1 shifts the graph to the left, that is, towards negative values of x .

For example, if f ( x ) = x 2 , then g ( x ) = ( x 2 ) 2 is a new function. Each input is reduced by 2 prior to squaring the function. The result is that the graph is shifted 2 units to the right, because we would need to increase the prior input by 2 units to yield the same output value as given in f .

Horizontal shift

Given a function f , a new function g ( x ) = f ( x h ) , where h is a constant, is a horizontal shift    of the function f . If h is positive, the graph will shift right. If h is negative, the graph will shift left.

Adding a constant to an input

Returning to our building airflow example from [link] , suppose that in autumn the facilities manager decides that the original venting plan starts too late, and wants to begin the entire venting program 2 hours earlier. Sketch a graph of the new function.

We can set V ( t ) to be the original program and F ( t ) to be the revised program.

V ( t ) =  the original venting plan F ( t ) = starting 2 hrs sooner

In the new graph, at each time, the airflow is the same as the original function V was 2 hours later. For example, in the original function V , the airflow starts to change at 8 a.m., whereas for the function F , the airflow starts to change at 6 a.m. The comparable function values are V ( 8 ) = F ( 6 ) . See [link] . Notice also that the vents first opened to 220  ft 2 at 10 a.m. under the original plan, while under the new plan the vents reach 220  ft 2 at 8 a.m., so V ( 10 ) = F ( 8 ) .

In both cases, we see that, because F ( t ) starts 2 hours sooner, h = 2. That means that the same output values are reached when F ( t ) = V ( t ( 2 ) ) = V ( t + 2 ) .

Figure_01_05_005a
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Questions & Answers

The average annual population increase of a pack of wolves is 25.
Brittany Reply
how do you find the period of a sine graph
Imani Reply
Period =2π if there is a coefficient (b), just divide the coefficient by 2π to get the new period
Am
if not then how would I find it from a graph
Imani
by looking at the graph, find the distance between two consecutive maximum points (the highest points of the wave). so if the top of one wave is at point A (1,2) and the next top of the wave is at point B (6,2), then the period is 5, the difference of the x-coordinates.
Am
you could also do it with two consecutive minimum points or x-intercepts
Am
I will try that thank u
Imani
Case of Equilateral Hyperbola
Jhon Reply
ok
Zander
ok
Shella
f(x)=4x+2, find f(3)
Benetta
f(3)=4(3)+2 f(3)=14
lamoussa
14
Vedant
pre calc teacher: "Plug in Plug in...smell's good" f(x)=14
Devante
8x=40
Chris
Explain why log a x is not defined for a < 0
Baptiste Reply
the sum of any two linear polynomial is what
Esther Reply
divide simplify each answer 3/2÷5/4
Momo Reply
divide simplify each answer 25/3÷5/12
Momo
how can are find the domain and range of a relations
austin Reply
the range is twice of the natural number which is the domain
Morolake
A cell phone company offers two plans for minutes. Plan A: $15 per month and $2 for every 300 texts. Plan B: $25 per month and $0.50 for every 100 texts. How many texts would you need to send per month for plan B to save you money?
Diddy Reply
6000
Robert
more than 6000
Robert
can I see the picture
Zairen Reply
How would you find if a radical function is one to one?
Peighton Reply
how to understand calculus?
Jenica Reply
with doing calculus
SLIMANE
Thanks po.
Jenica
Hey I am new to precalculus, and wanted clarification please on what sine is as I am floored by the terms in this app? I don't mean to sound stupid but I have only completed up to college algebra.
rachel Reply
I don't know if you are looking for a deeper answer or not, but the sine of an angle in a right triangle is the length of the opposite side to the angle in question divided by the length of the hypotenuse of said triangle.
Marco
can you give me sir tips to quickly understand precalculus. Im new too in that topic. Thanks
Jenica
if you remember sine, cosine, and tangent from geometry, all the relationships are the same but they use x y and r instead (x is adjacent, y is opposite, and r is hypotenuse).
Natalie
it is better to use unit circle than triangle .triangle is only used for acute angles but you can begin with. Download any application named"unit circle" you find in it all you need. unit circle is a circle centred at origine (0;0) with radius r= 1.
SLIMANE
What is domain
johnphilip
the standard equation of the ellipse that has vertices (0,-4)&(0,4) and foci (0, -15)&(0,15) it's standard equation is x^2 + y^2/16 =1 tell my why is it only x^2? why is there no a^2?
Reena Reply
what is foci?
Reena Reply
This term is plural for a focus, it is used for conic sections. For more detail or other math questions. I recommend researching on "Khan academy" or watching "The Organic Chemistry Tutor" YouTube channel.
Chris
how to determine the vertex,focus,directrix and axis of symmetry of the parabola by equations
Bryssen Reply

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Source:  OpenStax, Precalculus. OpenStax CNX. Jan 19, 2016 Download for free at https://legacy.cnx.org/content/col11667/1.6
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