Parametric Equations
x=f(t), y=g(t) defining a curve via parameter t.
Example: Unit circle: x=cos t, y=sin t.

Read the notes, then try the practice. It adapts as you go.When you're ready.
Session Length
~11 min
Adaptive Checks
10 questions
Transfer Probes
7
This topic covers parametric equations, polar coordinates, and vector-valued functions for AP Calculus BC Unit 9. Parametric equations describe curves via x=f(t),y=g(t).
Polar coordinates use (r,theta). Vector-valued functions unify position, velocity, and acceleration. Key skills: parametric derivatives, polar area/arc length, vector motion analysis.
One step at a time.
Adjust the controls and watch the concepts respond in real time.
x=f(t), y=g(t) defining a curve via parameter t.
Example: Unit circle: x=cos t, y=sin t.
dy/dx = (dy/dt)/(dx/dt), dx/dt \!= 0.
Example: x=t^2,y=t^3: dy/dx=3t/2.
Point (r,theta): distance and angle from origin.
Example: (1,pi/4) = (sqrt2/2,sqrt2/2).
A = (1/2) int r^2 dtheta.
Example: r=2costh: A=pi.
L = int sqrt((dx/dt)^2+(dy/dt)^2) dt.
Example: Unit circle: L=2pi.
r(t)=<x(t),y(t)>.
Example: <t,t^2> traces y=x^2.
|v(t)| = sqrt(x_prime^2 + y_prime^2).
Example: v=<3,4>: speed=5.
Choose a different way to engage with this topic — no grading, just richer thinking.
Explore your way — choose one:
See how the key ideas connect. Nodes color in as you practice.
Walk through a solved problem step-by-step. Try predicting each step before revealing it.
This is guided practice, not just a quiz. Hints and pacing adjust in real time.
Small steps add up.
What you get while practicing:
The best way to know if you understand something: explain it in your own words.
More ways to strengthen what you just learned.