Cos 125 Degrees
Sin, Cos, Tan, Cot of an Angle
What is cos 125°?
Answer
cos 125° ≈
−0.5736
Angle in radians: 125° = 25π/36. The point of the angle is in quadrant II, where cosine is negative.
≈ — rounded to 4 decimal places. cos 125° can't be written with square roots: 125° is not a multiple of 3°.
cos 125° = cos(180° − 55°) = −cos 55° ≈ −0.5736
P(cos 125°, sin 125°) ≈ (−0.5736, 0.8192)
P(cos 125°, sin 125°) ≈ (−0.5736, 0.8192)
Highlighted: the projection on the x-axis — cosine, x ≈ −0.5736.
See Also
- Arcsin, Arccos, Arctan, Arccot - The angle from the value of its sine, cosine, tangent or cotangent: exact in degrees and π, with the check and the unit circle
- Square Root Calculator - Calculate the square root of any number
- Simplify Square Root Calculator - Write any square root in simplest radical form, step by step
- Geometry Formulas: Area, Volume, Perimeter - The formula for every standard shape, where it comes from, and worked examples
Cosine of nearby angles
FAQ
What is cos 125°?
cos 125° ≈ −0.5736
Why does cos 125° have no exact value?
A trigonometric value of a whole number of degrees can be written with square roots only when the angle is a multiple of 3°. 125° is not, so no such exact form exists; the value is used as a decimal: cos 125° ≈ −0.5736.
Why does a calculator show 0.7877 for cos 125?
The calculator is in radian mode (RAD): it takes cos 125 as the cosine of 125 radians, cos 125 rad ≈ 0.7877. Switch it to degrees (DEG): cos 125° ≈ −0.5736. In radians the value is never undefined: π is irrational, so a whole number of radians never lands exactly on an axis.
See Also
- Cos 90 Degrees: Cosine of 90° on the Unit Circle
- Cos 97 Degrees: Cosine of 97° on the Unit Circle
- Cos 98 Degrees: Cosine of 98° on the Unit Circle
- Cos 100 Degrees: Cosine of 100° on the Unit Circle
- Cos 101 Degrees: Cosine of 101° on the Unit Circle
- Cos 105 Degrees: Cosine of 105° on the Unit Circle
- Cos 106 Degrees: Cosine of 106° on the Unit Circle
- Cos 108 Degrees: Cosine of 108° on the Unit Circle
- Cos 110 Degrees: Cosine of 110° on the Unit Circle
- Cos 120 Degrees: Cosine of 120° on the Unit Circle
- Cos 126 Degrees: Cosine of 126° on the Unit Circle
- Cos 127 Degrees: Cosine of 127° on the Unit Circle
- Cos 130 Degrees: Cosine of 130° on the Unit Circle
- Cos 134 Degrees: Cosine of 134° on the Unit Circle
- Cos 135 Degrees: Cosine of 135° on the Unit Circle
- Cos 140 Degrees: Cosine of 140° on the Unit Circle
- Cos 142 Degrees: Cosine of 142° on the Unit Circle
- Cos 144 Degrees: Cosine of 144° on the Unit Circle
- Cos 145 Degrees: Cosine of 145° on the Unit Circle
- Cos 150 Degrees: Cosine of 150° on the Unit Circle
- Косинус 125 градусов (cos 125°) на единичной окружности
- Coseno de 125 grados (cos 125°) en el círculo unitario
- Cosseno de 125 graus (cos 125°) no ciclo trigonométrico