00:01
In this problem, we're given the function f of x equals the square root of the quantity x minus 1.
00:08
The first goal of this problem is to determine whether or not the function f of x is a 1 -to -one function.
00:14
The easiest way to do this is to graph the function f and then perform a horizontal line test.
00:20
I'm going to my graphic calculator and type in the function y equals i'm going to say x minus 1, close quantity, the one -half power.
00:36
It's something to the one -half power.
00:38
It's the same thing as taking the square root of it.
00:41
Here's the function.
00:45
Now, if i draw any arbitrary horizontal line straight through the function, f of x, i can see that any horizontal line only crosses the function once.
00:59
There's one intersection point.
01:01
It never crosses the line, but f of x more than once...