Arcsin of 2/5

Arcsin, Arccos, Arctan, Arccot
Function
x

What is arcsin(2/5)?

Answer

arcsin(2/5) ≈
23.5782° ≈ 0.4115 rad

Range: arcsin x is an angle from −90° to 90°, so the answer is unique.

≈ — the value is not a table one; rounded to 4 decimal places.

2/5 = 0.4.

arcsin(2/5) is the angle α in [−90°, 90°] with sin α = 2/5.

sin 23.5782° ≈ 0.4000

xyOP

α = arcsin(2/5) ≈ 23.5782°

P ≈ (0.9165, 0.4)

P lies on the line y = 2/5 in the right half of the circle, where cos α ≥ 0; highlighted: sin α = 2/5.

All four inverse functions of 2/5
FunctionDegreesRadians
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

Recalculate with different values ↑

Arcsine of nearby values

xarcsin x
1/5≈ 11.5370°
1/4≈ 14.4775°
0.3≈ 17.4576°
2/5≈ 23.5782°
1/230° = π/6
3/5≈ 36.8699°
2/3≈ 41.8103°

FAQ

What is arcsin(2/5)?

arcsin(2/5) ≈ 23.5782° ≈ 0.4115 rad

How to convert arcsin(2/5) to radians?

Multiply the angle in degrees by π/180: 23.5782° × π/180 ≈ 0.4115 rad.

Why does a calculator show 0.4115 for arcsin(2/5)?

The calculator is in radian mode (RAD) and gives the angle in radians: arcsin(2/5) ≈ 0.4115 rad. In degrees (DEG) it is ≈ 23.5782°.

See Also