Pythagorean theorem
Find a missing side in a right triangle. Choose whether the missing side is the longest hypotenuse or one of the two perpendicular legs.
MAKE THE FORMULA CLEAR
Trigonometric functions
Calculate sine, cosine and tangent or recover a principal angle from a function value. Check degrees versus radians before calculating.
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Result of sin
0.5
Inverse trigonometric functions find an angle from a ratio. Forward functions find a ratio from an angle.
Worked steps
- Calculated using degrees
- sin(30°)＝0.5
Forward functions use your selected angle unit and return dimensionless values. Inverse functions take a function value and return an angle in the selected unit. Inverse results are principal values, not every periodic solution. Near undefined tangent points, no huge approximate result is shown.
Method and scope
Ordinary functions take an angle in the selected unit and return a unitless ratio. Inverse functions take a ratio and return an angle in that unit.
Inverse sine and cosine require values from -1 to 1. Principal inverse values do not list every angle with the same periodic function value.
Tangent is undefined at odd multiples of 90 degrees, and near-undefined cases are not shown as huge misleading approximations. Numerical results are approximations, not symbolic expressions.
What this helps you do
Calculate sine, cosine and tangent or recover a principal angle from a function value. Check degrees versus radians before calculating.
What to enter
Start with function, then fill the other relevant fields in the units shown. The field hints explain the required format and examples.
How the calculation works
Ordinary functions take an angle in the selected unit and return a unitless ratio. Inverse functions take a ratio and return an angle in that unit.
Worked example
Sine of 30 degrees is 0.5. Arcsine of 0.5 returns 30 degrees, or about 0.523599 radians when radians are selected.
Understanding the answer
Inverse sine and cosine require values from -1 to 1. Principal inverse values do not list every angle with the same periodic function value.
Scope and limitations
Tangent is undefined at odd multiples of 90 degrees, and near-undefined cases are not shown as huge misleading approximations. Numerical results are approximations, not symbolic expressions.