Arccos of 4/5
Arcsin, Arccos, Arctan, Arccot
What is arccos(4/5)?
Answer
arccos(4/5) ≈
36.8699° ≈ 0.6435 rad
Range: arccos x is an angle from 0° to 180°, so the answer is unique.
≈ — the value is not a table one; rounded to 4 decimal places.
4/5 = 0.8.
arccos(4/5) is the angle α in [0°, 180°] with cos α = 4/5.
cos 36.8699° ≈ 0.8000
α = arccos(4/5) ≈ 36.8699°
P = (0.8, 0.6)
P lies on the line x = 4/5 in the upper half of the circle, where sin α ≥ 0; highlighted: cos α = 4/5.
| Function | Degrees | Radians |
|---|---|---|
| arcsin(4/5) | ≈ 53.1301° | ≈ 0.9273 |
| arccos(4/5) | ≈ 36.8699° | ≈ 0.6435 |
| arctan(4/5) | ≈ 38.6598° | ≈ 0.6747 |
| arccot(4/5) | ≈ 51.3402° | ≈ 0.8961 |
See Also
- Sin, Cos, Tan, Cot of an Angle - Exact value in square roots and the decimal, with reduction to an acute angle on 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
Arccosine of nearby values
| x | arccos x |
|---|---|
| 0.7 | ≈ 45.5730° |
| √2/2 | 45° = π/4 |
| 3/4 | ≈ 41.4096° |
| 4/5 | ≈ 36.8699° |
| √3/2 | 30° = π/6 |
| 0.9 | ≈ 25.8419° |
| 12/13 | ≈ 22.6199° |
FAQ
What is arccos(4/5)?
arccos(4/5) ≈ 36.8699° ≈ 0.6435 rad
How to convert arccos(4/5) to radians?
Multiply the angle in degrees by π/180: 36.8699° × π/180 ≈ 0.6435 rad.
Why does a calculator show 0.6435 for arccos(4/5)?
The calculator is in radian mode (RAD) and gives the angle in radians: arccos(4/5) ≈ 0.6435 rad. In degrees (DEG) it is ≈ 36.8699°.
See Also
- Arccos of 1 (Inverse Cosine) in Degrees and Radians
- Arccos of 1/2 (Inverse Cosine) in Degrees and Radians
- Arccos of 1/3 (Inverse Cosine) in Degrees and Radians
- Arccos of 1/4 (Inverse Cosine) in Degrees and Radians
- Arccos of 1/5 (Inverse Cosine) in Degrees and Radians
- Arccos of 2 (Inverse Cosine) in Degrees and Radians
- Arccos of 2/3 (Inverse Cosine) in Degrees and Radians
- Arccos of 2/5 (Inverse Cosine) in Degrees and Radians
- Arccos of 3/4 (Inverse Cosine) in Degrees and Radians
- Arccos of 3/5 (Inverse Cosine) in Degrees and Radians
- Arccos of 4/7 (Inverse Cosine) in Degrees and Radians
- Arccos of 12/13 (Inverse Cosine) in Degrees and Radians
- Arccos of 60 (Inverse Cosine) in Degrees and Radians
- Arccos of √2/2 (Inverse Cosine) in Degrees and Radians
- Arccos of √3/2 (Inverse Cosine) in Degrees and Radians
- Arccos of √3/3 (Inverse Cosine) in Degrees and Radians
- Arccot of −1 (Inverse Cotangent) in Degrees and Radians
- Arccot of −2 (Inverse Cotangent) in Degrees and Radians
- Arccot of −√3 (Inverse Cotangent) in Degrees and Radians
- Arccot of −√3/3 (Inverse Cotangent) in Degrees and Radians
- Арккосинус 4/5 (arccos 4/5) в градусах и радианах
- Arcocoseno de 4/5 (arccos 4/5) en grados y radianes
- Arco cosseno de 4/5 (arccos 4/5) em graus e radianos