Concept 5
Convert between degrees and radians when needed (SAT).
Degrees and radians are just two ways to write the same angle. Convert with the standard pi-based factor in the direction the question asks for.
Core Idea
Understanding
Rule: Degrees and radians are the same angle measure written in different units.
- Use
radians𝜋 as the conversion bridge.= 1 8 0 ∘ - Multiply by
to go degrees𝜋 1 8 0 radians.→ - Multiply by
to go radians1 8 0 𝜋 degrees.→
Memorize the common benchmarks:
Step by Step
- Degrees → radians: multiply by
.𝜋 1 8 0 - Radians → degrees: multiply by
.1 8 0 𝜋 - Simplify the fraction.
Misconceptions
- Multiplying by
when converting from degrees to radians (that's the wrong direction).1 8 0 𝜋 - Leaving
out of radian answers — radians must include𝜋 unless fully evaluated.𝜋 - Confusing
°) with𝜋 6 ( 3 0 °).𝜋 3 ( 6 0
Question
Worked Example
What is
Select an answer to see the explanation