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Example Questions
Example Question #5 : Understanding Functions
The polynomial function has zeroes at
and
. Which of the following could be the graph of
in the
plane?
On a problem such as this that asks you to match a graph with a function, you need to use process of elimination using the characteristics of the function that you were provided. Here you're told where the zeroes are, meaning that at those points, and
, the graph should cross the x-axis. Only one graph meets those criteria, so you have your correct answer.
Example Question #6 : Understanding Functions
If n is a constant in the function f(x) = nx + 5, and f(14) = -2, what is f(2)?
4
4
In this instance, we can use the outcome of the function when our input is 14 to solve for “n” and thus, understand our full function. If
f(14) = -2 and f(x) = nx + 5, then
n(14) + 5 = -2
If we isolate n, we arrive at
n(14) = -7
Be careful… we can’t stop here! The question hasn’t asked us to solve for n, it has asked us for f(2). So, if we know that our function, with n as a known constant, is
, then
, or 4.
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