00:01
So for this problem, we're solving for a dydx at x is equal to 1.
00:05
But we can see that when we look at our equation for y, we have y in terms of t.
00:09
And we also have an equation for t in terms of x.
00:12
But if we think about what happens when we take the derivative, we know that for dy, we would take the derivative of dy with respect to t.
00:19
And if we take the derivative of t with respect to x, we're going to get dtdx.
00:24
So if we multiply these two terms together, we're going to be able to cancel out these dts and just be left with dydx.
00:31
So essentially we just need to find the derivative of each of these individual functions.
00:35
So we can start by finding dydt, and we can see that we're going to need to use the quotient rule here.
00:42
So we start by finding the derivative of the numerator, which in this case is just 2t, times the denominator unchanged, which will be times t squared minus 2.
00:51
And we're going to subtract the numerator unchanged, so t squared plus 2, times the derivative of our denominator, which is just 2t.
00:58
And this is divided by our denominator squared, which will be t squared minus 2 squared.
01:05
And we can go ahead and simplify this.
01:07
And we can see that when we factor this, or excuse me, distribute this out, we're going to essentially just be left with our numerator of negative 8t, and this is over our denominator of t squared minus 2 squared...