Question

Explain how to use a graph of the function f(x) to find f(3).

Answer 1

To find the value of f(3) we need to follow the below steps :

Step 1 : First plot the graph of f(x)

Step 2 : We need to find f(3) or the function value at x = 3 therefore, in the graph locate the point (3,0)

Step 3 : Draw a line parallel to Y-axis passing through the point (3,0) .

Step 4 : Now there exists two cases :

If the drawn line do not intersect the graph of f(x), then no value of f(3) exists for the given function of x

If the drawn line intersects the graph, then the intersection point is marked and a line parallel to x - axis is drawn passing through that marked or intersection point. And the line where it intersects the y - axis is our required value of f(3).

If this is wrong than I guess I wasn't smart enough :)