McGraw Hill Glencoe Algebra 2, 2012
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McGraw Hill Glencoe Algebra 2, 2012 View details
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Exercise 31 Page 440

What differences do you see between the given function and the parent function? Apply those transformations to the graph of the parent function, f(x)=sqrt(x).

Graph:

Domain: x≥0
Range: f(x) ≥ 0

Practice makes perfect

The given function is a square root function. The graph of it will be a transformed version of the parent function, y=sqrt(x). Square root functions typically follow the same general format. f(x)=asqrt(x- h)+ k To graph the given square root function, let's put it in general form first. f(x)=sqrt(3x) ⇔ f(x)=sqrt(3)sqrt(x- 0)+ 0

Graphing the Function

To graph the given function, let's show the possible transformations of f(x)=sqrt(x).

Transformations of f(x)
Vertical Translations Translation up k units, k>0 y=f(x)+ k
Translation down k units, k>0 y=f(x)- k
Horizontal Translations Translation right h units, h>0 y=f(x- h)
Translation left h units, h>0 y=f(x+ h)
Vertical Stretch or Shrink Vertical stretch, a>1 y= af(x)
Vertical shrink, 0< a<1 y= af(x)
Reflections In the x-axis y= - f(x)
In the y-axis y= f(- x)

Using the table, we can graph the function. Let's begin with the parent function.

Now, we will multiply the y-coordinates by a=sqrt(3). This stretches the parent graph by a factor of sqrt(3).

Since h and k are zero, neither horizantal nor vertical translation is needed. Thus, we have the graph of the given function.

Finding the Domain and Range

To determine the domain of the function, recall that the radicand cannot be negative. 3x ≥ 0 ⇔ x ≥ 0 Therefore, the possible values of x are those such that x≥ 0. By substituting the minimum value of the domain into the function, we can find the minimum value of the range.

f(x)=sqrt(3x)
f( 0)=sqrt(3( 0))
f(0)=0

This tells us that the range is all values of f(x) such that f(x)≥ 0. Domain:& x ≥ 0 Range:& f(x)≥ 0