Exam Strategy
Readiness Check
You are ready when you can:
- Convert points both directions with correct theta.
- Plot/locate points from either form.
- Write complex numbers in a+bi and polar trig form.
- Explain multiple polar representations when relevant.
On the AP Exam
- MCQ: conversion, quadrant angle, complex modulus/argument.
- FRQ: convert with justification (skills 1.B, 2.A).
Tactics
1. Label quadrant before finding theta. 2. Compute r = sqrt(x^2+y^2) first when going rect to polar. 3. For x>0, theta = arctan(y/x); adjust with +pi or +pi/2 rules as needed. 4. Check: x should equal r cos theta and y equal r sin theta. 5. Complex: r = |a+bi| = sqrt(a^2+b^2).
Common Traps
- Wrong quadrant theta.
- Using degrees vs radians inconsistently.
- Forgetting i in complex polar sine term.
- Assuming polar coordinates are unique.
Quick Checklist
- [ ] Formulas correct
- [ ] Quadrant checked
- [ ] r nonnegative if required
- [ ] Back-substitution verified
- [ ] Complex forms complete