Cos 65 Degrees
Sin, Cos, Tan, Cot of an Angle
What is cos 65°?
Answer
cos 65° ≈
0.4226
Angle in radians: 65° = 13π/36. The point of the angle is in quadrant I, where cosine is positive.
≈ — rounded to 4 decimal places. cos 65° can't be written with square roots: 65° is not a multiple of 3°.
P(cos 65°, sin 65°) ≈ (0.4226, 0.9063)
P(cos 65°, sin 65°) ≈ (0.4226, 0.9063)
Highlighted: the projection on the x-axis — cosine, x ≈ 0.4226.
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 65°?
cos 65° ≈ 0.4226
Why does cos 65° 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°. 65° is not, so no such exact form exists; the value is used as a decimal: cos 65° ≈ 0.4226.
Why does a calculator show −0.5625 for cos 65?
The calculator is in radian mode (RAD): it takes cos 65 as the cosine of 65 radians, cos 65 rad ≈ −0.5625. Switch it to degrees (DEG): cos 65° ≈ 0.4226. 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 55 Degrees: Cosine of 55° on the Unit Circle
- Cos 56 Degrees: Cosine of 56° on the Unit Circle
- Cos 57 Degrees: Cosine of 57° on the Unit Circle
- Cos 58 Degrees: Cosine of 58° on the Unit Circle
- Cos 59 Degrees: Cosine of 59° on the Unit Circle
- Cos 60 Degrees: Cosine of 60° on the Unit Circle
- Cos 61 Degrees: Cosine of 61° on the Unit Circle
- Cos 62 Degrees: Cosine of 62° on the Unit Circle
- Cos 63 Degrees: Cosine of 63° on the Unit Circle
- Cos 64 Degrees: Cosine of 64° on the Unit Circle
- Cos 66 Degrees: Cosine of 66° on the Unit Circle
- Cos 67 Degrees: Cosine of 67° on the Unit Circle
- Cos 68 Degrees: Cosine of 68° on the Unit Circle
- Cos 69 Degrees: Cosine of 69° on the Unit Circle
- Cos 70 Degrees: Cosine of 70° on the Unit Circle
- Cos 71 Degrees: Cosine of 71° on the Unit Circle
- Cos 72 Degrees: Cosine of 72° on the Unit Circle
- Cos 73 Degrees: Cosine of 73° on the Unit Circle
- Cos 74 Degrees: Cosine of 74° on the Unit Circle
- Cos 75 Degrees: Cosine of 75° on the Unit Circle
- Косинус 65 градусов (cos 65°) на единичной окружности
- Coseno de 65 grados (cos 65°) en el círculo unitario
- Cosseno de 65 graus (cos 65°) no ciclo trigonométrico