00:01
This problem says the functions f and g are defined as follows, where f of x equals negative 3x plus 2 and g of x equals 3x squared minus 3x, and we're asked to find f of 4 and g of negative 5 and to simplify our answers as much as possible.
00:14
So first for f of 4, we're given the input value of 4 to evaluate with, and we need to make sure to match with the right function.
00:22
So if we want f of 4, that means we're going to go to f of x and substitute in 4 for x and evaluate the expression.
00:29
So this will become negative 3, not times x anymore, but times 4 plus 2.
00:34
So that gives us negative 3 times 4, which is negative 12, still plus 2.
00:40
And negative 12 plus 2 gives us negative 10.
00:42
So that means that f of 4 is equal to negative 10.
00:46
For g of negative 5, we're going to do the same thing.
00:49
But this time our input value that we're putting in for x is negative 5.
00:53
And also we're looking at the g of x function instead of f of x.
00:56
So we're going to replace the x value of x squared and x for 3x squared minus 3x with negative 5...