Trigonometry Calculator

Calculate sine, cosine, tangent, and inverse functions (arcsin, arccos, arctan). Input in DEGREES (most intuitive). For radians, convert: degrees × π / 180. Used in: physics, engineering, surveying, navigation, architecture, computer graphics, signal processing.

Details

sin(θ) = opposite / hypotenuse

cos(θ) = adjacent / hypotenuse

tan(θ) = opposite / adjacent = sin/cos

Common values: sin(30) = 0.5, sin(60) = 0.866, sin(90) = 1

Tips

• sin and cos always between -1 and 1
• tan undefined at 90° (cos = 0, division by zero)
• Inverse functions return angles
• Calculator uses degrees — multiply by π/180 to convert to radians
• Real-world: angle of inclination, refraction, projectile motion

FAQs

Why does sin(30) = 0.5?

In 30-60-90 right triangle, side opposite 30° angle is exactly half the hypotenuse. So sin(30) = 0.5 by definition.

What's arctan(1)?

45° — because tan(45) = 1 (opposite = adjacent in 45-45-90 triangle).

Degrees vs radians?

Degrees: 0-360 (intuitive). Radians: 0-2π (used in calculus, physics). 1 radian = 57.3°.