How do I find the equation of the tangent line to the curve y=2xcos(x) at the point (pi, -2pi)? The equation of this tangent line can be written in the form y=mx+b where m and b are?
I know how to do these when I'm given regular numbers, not trig stuff. You just find the derivative and plug in what they want, but I'm really confused with how to do this on a unit circle...
I know how to do these when I'm given regular numbers, not trig stuff. You just find the derivative and plug in what they want, but I'm really confused with how to do this on a unit circle...
1 Answer
Explanation:
Given your comment, I'll skip on the initial details: as you said, we must compute the derivative and plug the correct values. If you get confused with
We compute the derivative:
The derivative returns the slope of the tangent line for any given
We know that
So, the slope of the tangent line is
At this point, we want the equation of a line passing through a given point with a given slope. There's a formula for cases like this:
In our case,
which we can rewrite into
And thus we have the answer