SOLUTION: here is the problem, but I am not sure if it is going to read correctly or not, any help would bea pparecaited as I have nearly losted it on this one: For the function f(x) find

Algebra ->  Coordinate-system -> SOLUTION: here is the problem, but I am not sure if it is going to read correctly or not, any help would bea pparecaited as I have nearly losted it on this one: For the function f(x) find      Log On


   



Question 192947: here is the problem, but I am not sure if it is going to read correctly or not, any help would bea pparecaited as I have nearly losted it on this one:
For the function f(x) find f(-2) and graph the function.
f(x)= {3x+5 x< -2
{x+2 x>= -2
*note the bracket is just one large bracket on the left not two*

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!


Remember, a piecewise function is simply a function composed of different functions. These functions are defined on "pieces" of the domain. So in the case of the given function



the two equations y=3x%2B5 and y=x%2B2 are defined for x%3C-2 and x%3E=-2 respectively. So what this means is that you graph the equation y=3x%2B5 ONLY if x%3C-2. Otherwise, you graph y=x%2B2 (since it is defined for x%3E=-2)


So the graph will look like this:



Graph of the given piecewise function where the red line is y=3x%2B5 (only drawn if x%3C-2) the green line is y=x%2B2 (only drawn if x%3E=-2)

Note: there is an open circle at (-2,-1) and a closed circle at (-2,0).


So because -2%3E=-2, this means that we'll use y=x%2B2 to find f%28-2%29

Because the function f%28x%29=x%2B2 is defined for values x%3E=-2, this means that f%28-2%29=-2%2B2=0


f%28x%29=x%2B2 Start with the second expression of the piecewise function


f%28-2%29=-2%2B2 Plug in x=-2


f%28-2%29=0 Add


So f%28-2%29=0