00:01
We're going to be finding an equation for the tangent line to this function at x is equal to 1.
00:05
So we're going to have to find the derivative of this function, but first we're also going to have to find the y value that corresponds with this x value.
00:13
So let's go ahead and plug in x is equal to 1.
00:15
So we'd have y is equal to 1 to the 1 plus 2 power, which is just 1.
00:21
And so we're looking at the point 1 comma 1.
00:24
Now the next thing we can do is take the derivative of this function.
00:27
In order to take the derivative, we're going to first have to take the natural log, both sides.
00:30
So we're going to be using logarithmic differentiation.
00:34
So we have the natural log of y is equal to the natural log of x, the x plus two power.
00:39
We can take this x plus two and put it out front due to the properties of natural logs.
00:44
So we have the natural log of y is equal to x plus two times the natural log of x.
00:50
Now we can take the derivative of both sides.
00:53
On the left side, we're going to get y -prime divided by y, or one divided by y times y prime.
00:58
And on the left side, this is going to be a product rule derivative.
01:03
So we're going to have the derivative of x plus 2, which is just one times the natural log of x.
01:08
So it's just going to be the natural log of x, and then plus x plus 2 times the derivative of the natural log of x, which is 1 divided by x.
01:15
So we're going to have x plus 2 divided by x there...