Half Angle Calculator sin(θ/2), cos(θ/2), tan(θ/2). Angle (degrees) sin(θ/2) 0.5 cos(θ/2) 0.866 tan(θ/2) 0.5774 Step-by-step with your numbers: 1. Values used: 2. Angle = 60 degrees 3. sin(θ/2) = 0.5 4. cos(θ/2) = 0.866 5. tan(θ/2) = 0.5774 Did we solve your problem today? 👍 Yes 👎 No Thanks for the feedback! Just halve the angle and apply trig. FAQ Formulas? sin(θ/2)=±√((1−cosθ)/2). Related calculators Double Angle Calculator sin(2θ), cos(2θ), tan(2θ). Trigonometry Calculator Find sine, cosine and tangent of an angle.