7.0k views
1 vote
Find an equation of the tangent line to the curve at the point corresponding to the given value of the parameter. x = t cos(t), y = t sin(t); t =

1 Answer

2 votes


y = (-\pi )/(1+\pi ) . x + \pi

To find the equation of the tangent line to the curve x=tcos(t) and y=tsin(t) at the point corresponding to t=π, we'll follow the steps


(dx)/(dt) = cos(t) - tsin(t)


(dy)/(dt) = sin(t) - tcos(t)

at
t = \pi,


m = (sin (\pi ) + \pi cos (\pi ))/(cos(\pi) - \pi sin (\pi ) )


m = (-\pi )/(1+\pi )

Now, we need to find the point on the curve at
t = \pi


x_(0) = \pi cos (\pi ) = -\pi


y_(0) = \pi sin (\pi ) = 0

Plug in these values into the point-slope form:


y-0= (-\pi )/(1+\pi ) . (x + \pi)


y= (-\pi )/(1+\pi ) . (x + \pi)

That's the equation of the tangent line to the curve at the point corresponding to
t = \pi

Question
Find an Equation Given the Parameter:

User Dima Vishnyakov
by
7.4k points