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

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To evaluate f(2), f(-2), f^-1(0), and f^-1(2) for a parabola with a vertex at (-2,0), it's essential to first determine the function's equation. The inverse function swaps the x and y values, which simplifies finding the inverse coordinates. After sketching the inverse, the user successfully identified the coordinates for f(x) and then switched them to find the inverse values. The discussion emphasizes the need for more information about the function to accurately evaluate f(2) and f^-1. Ultimately, the user confirmed their understanding by evaluating the coordinates correctly.
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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
 
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Find the values of y when x equals each of those values for each graph. For example, find the y coordinate for the point on f(x) where x=2 to evaluate f(2). It may be useful to find the equations of the functions first. Try using the data and the graph to find the equations.
 
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:
 
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.
 
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:
 
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