Parametric functions, vector-valued functions, planar motion, matrices as transformations, and matrix operations and inverses as in the AP Precalculus Unit 4 topics.
39 cards · basic cards · AI-written, checked twice. Edit anything.
- What is a parametric equation?
Show answer
An equation in which both x and y are expressed as separate functions of a third variable (the parameter, usually t).
- In the parametric equations x = cos(t), y = sin(t), what does the parameter t represent?
Show answer
The angle measured from the positive x-axis on a circle of radius 1.
- What does 'eliminating the parameter' mean?
Show answer
Finding a single equation relating x and y by removing the parameter t from a pair of parametric equations.
- How does eliminating the parameter from x = 2t, y = 4t relate the variables?
Show answer
Solving for t from one equation and substituting into the other gives y = 2x.
- What is the formula for dy/dx when a curve is given parametrically?
Show answer
dy/dx = (dy/dt) / (dx/dt), provided dx/dt is not zero.
- What does the direction of a parametric curve show?
Show answer
As t increases, the direction indicates how the point moves along the curve (the orientation).
- How do you find d²y/dx² for a parametric curve?
Show answer
d²y/dx² = d/dt(dy/dx) / (dx/dt).
- How do you write a parametric equation for a line segment from (1, 2) to (5, 8)?
Show answer
x = 1 + 4t, y = 2 + 6t, where t goes from 0 to 1.
- What is a vector-valued function?
Show answer
A function that assigns a vector to each input value, usually written as r(t) = (f(t), g(t)).
- How do you express the parametric curve x = cos(t), y = sin(t) as a vector-valued function?
Show answer
r(t) = (cos(t), sin(t)).
- What does the position vector r(t) represent in planar motion?
Show answer
The location of a moving point at time t, given as r(t) = (x(t), y(t)).
- How do you find the velocity vector from the position vector r(t)?
Show answer
Take the derivative: v(t) = dr/dt = (dx/dt, dy/dt).
- How do you find the acceleration vector from the position vector r(t)?
Show answer
Take the second derivative: a(t) = d²r/dt² = (d²x/dt², d²y/dt²).
- What is the relationship between the velocity vector and the tangent line to a curve?
Show answer
The velocity vector is parallel to the tangent line; its direction gives the tangent direction.
- What is the speed of a moving object with velocity vector v(t) = (vx, vy)?
Show answer
speed = sqrt(vx^2 + vy^2), the magnitude of the velocity vector.