Cotangent Calculator
Calculate cot(θ) for any angle in degrees or radians — returns cos ÷ sin.
How it works
- 1Enter any angle and choose Degrees or Radians using the unit toggle.
- 2The calculator evaluates cot(θ) = cos(θ) ÷ sin(θ); boundary angles (0°, 180°, …) correctly return —.
- 3The result is displayed to 6 figures; — appears whenever sin(θ) = 0 and cotangent is undefined.
Use cases
- Solving oblique triangles and verifying trigonometric identities in precalculus and calculus.
- Engineering and physics problems involving slope, inclination, and wave analysis.
- Quick sanity-checking: cot(45°) = 1, cot(30°) ≈ 1.732, cot(60°) ≈ 0.577.
Frequently asked questions
Why does the calculator show — for 0°?
Cotangent is cos(θ) ÷ sin(θ). At 0° (and every multiple of 180°) sin(θ) = 0, making the expression undefined — like division by zero.
How does cotangent relate to tangent?
cot(θ) = 1 ÷ tan(θ); they are reciprocals. Wherever tan(θ) = 0 the cotangent is undefined, and vice versa.
Can I enter negative angles or angles over 360°?
Yes. Cotangent is periodic with period 180°, so cot(−45°) = cot(135°) = −1 and cot(405°) = cot(45°) = 1. Any real angle works.
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