Cogito
AP Precalculus · Chapter 7 · Lesson 1
Polar Coordinates
Locating a point by distance and direction.
12 problems · about 21 minutes · AP Precalculus 3.13, 3.14
Figure — use these to answer the problems
- Angle60° = π/3 rad
- x-coordinate0.500
- y-coordinate0.866
- cos 60°0.500
- sin 60°0.866
Warm Up
Straightforward practice. Get the method working first.
5 problemsThe rectangular point (8, 6). What is r?
AnswerWhat does r represent in a polar coordinate?
- The distance from the origin.
- The angle from the x-axis.
(5, 90°) in polar. What is the y-coordinate?
Answer(5, 90°) in polar. What is the x-coordinate?
AnswerThe rectangular point (6, 8). What is r?
Answer
Build It Up
The same ideas with more to keep track of.
3 problems(2, 180°) in polar. What is the x-coordinate?
AnswerThe rectangular point (0, 7). What is θ in degrees?
Answer(4, 270°) in polar. What is the y-coordinate?
Answer
Stretch Yourself
Mixed problems. Work out what kind of question it is before you start.
4 problemsWhich polar pairs name the same point as (3, 30°)?
- (3, 390 degrees)
- (negative 3, 210 degrees)
- (3, 60 degrees)
- (30, 3 degrees)
- Tick every box that applies.
The rectangular point (−5, 0). What is r?
AnswerThe Distance
The rectangular point (3, 4). What is r?
AnswerThe Coordinate
The polar point (6, 0°). What is its x-coordinate?
Answer