Cos 51 Degrees
Sin, Cos, Tan, Cot of an Angle
What is cos 51°?
Answer
cos 51° ≈
0.6293
Angle in radians: 51° = 17π/60. The point of the angle is in quadrant I, where cosine is positive.
≈ — rounded to 4 decimal places. An exact form of cos 51° in square roots exists, but it is unwieldy — nested radicals.
P(cos 51°, sin 51°) ≈ (0.6293, 0.7771)
P(cos 51°, sin 51°) ≈ (0.6293, 0.7771)
Highlighted: the projection on the x-axis — cosine, x ≈ 0.6293.
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 51°?
cos 51° ≈ 0.6293
Is there an exact value of cos 51°?
Yes: 51° is a multiple of 3°, and the values of such angles can be written with square roots — but the expression is unwieldy, with nested radicals built from the values of 18° and 15° (3° = 18° − 15°). In practice the decimal is used: cos 51° ≈ 0.6293.
Why does a calculator show 0.7422 for cos 51?
The calculator is in radian mode (RAD): it takes cos 51 as the cosine of 51 radians, cos 51 rad ≈ 0.7422. Switch it to degrees (DEG): cos 51° ≈ 0.6293. 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 41 Degrees: Cosine of 41° on the Unit Circle
- Cos 42 Degrees: Cosine of 42° on the Unit Circle
- Cos 43 Degrees: Cosine of 43° on the Unit Circle
- Cos 44 Degrees: Cosine of 44° on the Unit Circle
- Cos 45 Degrees: Cosine of 45° on the Unit Circle
- Cos 46 Degrees: Cosine of 46° on the Unit Circle
- Cos 47 Degrees: Cosine of 47° on the Unit Circle
- Cos 48 Degrees: Cosine of 48° on the Unit Circle
- Cos 49 Degrees: Cosine of 49° on the Unit Circle
- Cos 50 Degrees: Cosine of 50° on the Unit Circle
- Cos 52 Degrees: Cosine of 52° on the Unit Circle
- Cos 53 Degrees: Cosine of 53° on the Unit Circle
- Cos 54 Degrees: Cosine of 54° on the Unit Circle
- 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
- Косинус 51 градуса (cos 51°) на единичной окружности
- Coseno de 51 grados (cos 51°) en el círculo unitario
- Cosseno de 51 graus (cos 51°) no ciclo trigonométrico