By definition
Substituting these and the previously defined values gives
Multiplying by exp(-i*theta1) yields
Equating the imaginary parts and solving for alpha3 gives
Please enter the data to calculate the angular acceleration, alpha3.
Unit Type: SI US Customary Link lengths (m or ft): r2: r3: r4: rp: Angles: theta1: theta2: beta: Degree Mode Radian Mode omega2: Degrees/sec Radians/sec alpha2: Degrees/sec*sec Radians/sec*sec