Arctan of 2/5
Arcsin, Arccos, Arctan, Arccot
What is arctan(2/5)?
Answer
arctan(2/5) ≈
21.8014° ≈ 0.3805 rad
Range: arctan x is an angle strictly between −90° and 90°, so the answer is unique.
≈ — the value is not a table one; rounded to 4 decimal places.
2/5 = 0.4.
arctan(2/5) is the angle α in (−90°, 90°) with tan α = 2/5.
tan 21.8014° ≈ 0.4000
α = arctan(2/5) ≈ 21.8014°
P ≈ (0.9285, 0.3714)
T(1, 2/5) is where line OP meets the line x = 1; highlighted: tan α = 2/5.
| Function | Degrees | Radians |
|---|---|---|
| arcsin(2/5) | ≈ 23.5782° | ≈ 0.4115 |
| arccos(2/5) | ≈ 66.4218° | ≈ 1.1593 |
| arctan(2/5) | ≈ 21.8014° | ≈ 0.3805 |
| arccot(2/5) | ≈ 68.1986° | ≈ 1.1903 |
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
Arctangent of nearby values
| x | arctan x |
|---|---|
| 1/4 | ≈ 14.0362° |
| 0.3 | ≈ 16.6992° |
| 1/3 | ≈ 18.4349° |
| 2/5 | ≈ 21.8014° |
| 1/2 | ≈ 26.5651° |
| √3/3 | 30° = π/6 |
| 3/5 | ≈ 30.9638° |
FAQ
What is arctan(2/5)?
arctan(2/5) ≈ 21.8014° ≈ 0.3805 rad
How to convert arctan(2/5) to radians?
Multiply the angle in degrees by π/180: 21.8014° × π/180 ≈ 0.3805 rad.
Why does a calculator show 0.3805 for arctan(2/5)?
The calculator is in radian mode (RAD) and gives the angle in radians: arctan(2/5) ≈ 0.3805 rad. In degrees (DEG) it is ≈ 21.8014°.
See Also
- Arctan of 0.3 (Inverse Tangent) in Degrees and Radians
- Arctan of 0.7 (Inverse Tangent) in Degrees and Radians
- Arctan of 0.9 (Inverse Tangent) in Degrees and Radians
- Arctan of 1 (Inverse Tangent) in Degrees and Radians
- Arctan of 1/2 (Inverse Tangent) in Degrees and Radians
- Arctan of 1/3 (Inverse Tangent) in Degrees and Radians
- Arctan of 1/4 (Inverse Tangent) in Degrees and Radians
- Arctan of 1/5 (Inverse Tangent) in Degrees and Radians
- Arctan of 2 (Inverse Tangent) in Degrees and Radians
- Arctan of 2/3 (Inverse Tangent) in Degrees and Radians
- Arctan of 3 (Inverse Tangent) in Degrees and Radians
- Arctan of 3/2 (Inverse Tangent) in Degrees and Radians
- Arctan of 3/4 (Inverse Tangent) in Degrees and Radians
- Arctan of 3/5 (Inverse Tangent) in Degrees and Radians
- Arctan of 4 (Inverse Tangent) in Degrees and Radians
- Arctan of 4/5 (Inverse Tangent) in Degrees and Radians
- Arctan of 5 (Inverse Tangent) in Degrees and Radians
- Arctan of 5/2 (Inverse Tangent) in Degrees and Radians
- Arctan of 5/3 (Inverse Tangent) in Degrees and Radians
- Arctan of 5/6 (Inverse Tangent) in Degrees and Radians
- Арктангенс 2/5 (arctg 2/5) в градусах и радианах
- Arcotangente de 2/5 (arctan 2/5) en grados y radianes
- Arco tangente de 2/5 (arctg 2/5) em graus e radianos