Curve is moving towards the origin (if negative)
Curve is moving away from origin (if possible)
Back
dr/dt =
Front
dr/dθ (r') × dθ/dt
Back
Area with One Curve Inside and One Curve Outside
Front
- 2 integrals
- Same limits
- 1st Integral is the one with the area inside
- 2nd Integral is the one with the area outside
Back
What is the meaning of dx/dθ (bottom of slope equation)?
Front
Moving right (if positive)
Moving left (if negative)
Back
Graph: Rose Curve with Sine (Even)
Front
r=sin(nθ)
2n = # of petals
y-axis symmetry
Back
Find θ given an x or y coordinate
Front
1. Remember x = rcosθ and y = rsinθ (use respectively depending on which coordinate is given)
2. Plug in r (should be given)
3. Set expression equal to x/y coordinate
4. Put expression into y₁ in function mode
5. Put x/y coordinate into y₂ in function mode
6. Find the point of intersection
Back
Graph: Circle
Front
r= (a constant, that constant is the radius of the circle)
Back
Graph: Circle Shifted right/left
Front
r=ccos(θ)
c = constant
+ = right
- = left
Back
Graph: Lemniscate
Front
r²=a²cos(2θ)
Back
Graph: Rose Curve with Cosine (Even)
Front
r=cos(nθ)
2n = # of petals
x-axis symmetry
Back
How do you find max distance?
Front
(*Refer to 2005 AP Calculus BC Free Response Question 2 Part D)
1. Solve for r' (aka dr/dθ)
2. Set r' equal to 0 and solve
3. Make a t-chart with limits (interval) and value found from step 2
4. Plug θ values into r equation
Highest value is the maximum
Back
Graph: Cardioid with Cosine
Front
r=a+bcos(θ)
a=b
Back
y =
Front
rsin(θ)
Back
Graph: Rose Curve with Cosine (Odd)
Front
r=cos(nθ)
n = # of petals
x-axis symmetry
Back
Graph: Rose Curve with Sine (Odd)
Front
r=sin(nθ)
n = # of petals
y-axis symmetry
Back
How do you find dr/dθ or dy/dx in the calculator?
Front
dy/dx: 2nd → trace → 2 → type θ value (bar shows up at the bottom as you type it) → enter
dr/dθ: 2nd → trace → 3 → type θ value (bar shows up at the bottom as you type it) → enter
Back
x =
Front
rcos(θ)
Back
Graph: Line
Front
θ= # (in radians)
Back
Graph: Circle Shifted up/down
Front
r=csin(θ)
c = constant
+ = up
- = down
Back
What is the meaning of dy/dθ (top of slope equation)?
Front
Moving up (if positive)
Moving down (if negative)
Back
Graph: Cardioid with Sine
Front
r=a+bsin(θ)
a=b
Back
Vertical Tangent
Front
dx/dθ = 0
dy/dθ ≠ 0
Back
Horizontal Tangent
Front
dy/dθ = 0
dx/dθ ≠0
Back
Area Inside Both Curves
Front
- Think Perimeter!
c (½∫r² dθ + ½∫r² dθ)
c = constant (you may have to multiply accordingly)
*Limits aren't shown, but it would be from a to b in the first integral, and from b to c in the second integral