In a circle with radius r, the central angle of an arc with arc length of 3 π R / 4 =? Radians

In a circle with radius r, the central angle of an arc with arc length of 3 π R / 4 =? Radians


This is to use the arc length formula L = α * r
In a circle with radius r, the central angle of an arc with arc length of 3 π R / 4 = (3 π R / 4) / r = 3 π / 4 radians