Graph & Inverse: Evaluating f(2), f(-2), etc.

In summary, the conversation discusses finding the values of y for given x coordinates on a parabola graph with a vertex of (-2,0). The task is to evaluate f(2), f(-2), f^-1(0), and f^-1(2) by finding the equations of the functions and using the fact that inverses switch x and y values. The conversation concludes with the person finding the coordinates of f(x) and switching them to get the inverse, then using this information to evaluate the given values.
  • #1
aisha
584
0
I have a graph that looks like a C its a parabola and it has a vertex of -2,0 My question says to evaluate f(2) f(-2) f^-1(0) and f^-1(2) how do I do this? I sketched the inverse already now what? Please help me
 
Physics news on Phys.org
  • #2
Find the values of [itex]y[/itex] when [itex]x[/itex] equals each of those values for each graph. For example, find the [itex]y[/itex] coordinate for the point on [itex]f(x)[/itex] where [itex]x=2[/itex] to evaluate [itex]f(2)[/itex]. It may be useful to find the equations of the functions first. Try using the data and the graph to find the equations.
 
  • #3
Another thing: in an inverse the x and y values are switched. This fact makes drawing even the most complcated graph's inverses a breeze. :approve:
 
  • #4
Darned if I know! You will need to know more about the function than just that its graph "looks like a C its a parabola and it has a vertex of -2,0". From that, you can only say that f-1(0)= -2 since the inverse function swaps x and y values.
f(2) and f-1 depend upon other information about the graph.
 
  • #5
HallsofIvy said:
Darned if I know! You will need to know more about the function than just that its graph "looks like a C its a parabola and it has a vertex of -2,0". From that, you can only say that f-1(0)= -2 since the inverse function swaps x and y values.
f(2) and f-1 depend upon other information about the graph.


LOL thanks guys I got it, I found the coordinates of f(x) and then switched them to get the inverse. Then I evaluated I hope this is right. :smile:
 

FAQ: Graph & Inverse: Evaluating f(2), f(-2), etc.

1. What is a graph and inverse?

A graph is a visual representation of a function that shows the relationship between the input and output values. The inverse of a function is another function that reverses the input and output values of the original function.

2. How do you evaluate f(2) and f(-2) on a graph?

To evaluate f(2) and f(-2) on a graph, you need to locate the points with x-coordinates 2 and -2 on the x-axis. Then, you can find the corresponding y-coordinates on the y-axis. The points where the vertical lines through x=2 and x=-2 intersect the graph will give you the values of f(2) and f(-2).

3. What does f(2) and f(-2) represent on a graph?

f(2) and f(-2) represent the output values of a function when the input values are 2 and -2, respectively. In other words, they represent the y-coordinates of the points on the graph where the vertical lines through x=2 and x=-2 intersect the function.

4. How can you tell if a graph is symmetric about the line y=x?

A graph is symmetric about the line y=x if the inverse of the function is the same as the original function. This means that if you swap the x and y values of a point on the graph, it will still lie on the graph. You can also check for symmetry by folding the graph along the line y=x. If the two halves of the graph match up perfectly, then it is symmetric about the line y=x.

5. Can a graph and its inverse intersect more than once?

No, a graph and its inverse can only intersect once. This is because the inverse function reverses the input and output values of the original function, so any point that lies on both functions would have the same input and output values, making it the same point. Therefore, they can only intersect once at the point where x=y.

Back
Top