4-3-65
X
00:00
/
00:00
CC
On this problem, we know G of two is 1, so we have a point G
of two being one.
We know that the first derivative is positive.
It's a number between zero and one.
When X is less than two, the first derivative is positive.
We know we're increasing.
When we're less than two, the first derivative is going to be
close to one from the left side when we get closer and closer
and closer to two.
So if we look here versus here, we're getting closer and closer
and closer to the value of one for the actual derivative.
If we look at the next piece that says our first derivative
is a negative value when X is greater than two, If our first
derivative is a negative value when X is greater than two, it
means we're decreasing or we're going down our first derivative.
This is a typo.
Our first derivative has to go to -1 negative one for our slope
as the X is going to two from the right hand side.
So it's going to 1 positive one for our slope from the two to
the left, but -1 as we're going to two from the right.
That was part A.
Part B talks about G of two is going to be one.
Again, the 1st derivative is negative for X less than two.
If it's negative, we know it's going to be decreasing for X
less than two.
When our G prime of X gets close to two, our derivative is
getting close to negative Infinity.
So if we thought about putting in our lines here as tangents,
as we get closer and closer and closer, our line is going to get
more and more like a vertical line.
I get closer and closer and closer to this location, we're
going to have a vertical line.
So as X goes to two from the, oh, the left, so our first
derivative is positive when X is greater than two, IE we're going
out to Infinity.
So we're increasing there and the first derivatives going to
Infinity as X approaches 2 from the right.
So as we get closer and closer and closer, we're going to get
to positive Infinity over this direction.
We were going off to negative Infinity.
So our answer to that one is going to be C.