00:01
For this problem, we are asked to find the critical numbers of the function f of x equals x squared minus 3x minus 4, all divided by x minus 2.
00:08
And then we are to find the open intervals on which the function is increasing or decreasing and to locate all relative extrema.
00:15
And we are to use a graphing utility to confirm our results.
00:19
So to begin, we need to differentiate f of x.
00:24
We need to apply the quotient rule here.
00:26
So we'll have to do the derivative of the numerator, which will be 2x minus 3.
00:30
Times the denominator, minus the derivative of the denominator, 1 times the numerator, x squared minus 3, x minus 4, all divided by the denominator squared, so all over x minus 2 squared, which we can simplify down into the form x squared minus 4x plus 10, all over x minus 2 squared.
00:59
Now, we'll have that, if you want to, you can check this out by hand, but we'll find that this will never equal zero...