Robot inverse kinematics

I used GeoGebra to calculate the angles of a robot. - Drag point C to move the robot arm. - Robot arm length can be adjusted with the lever arm to the right.
The first angle of the first part of the robot is calculated by the angle V1 (DAC) + V2 (CAB) Next the angle between the first and the next part is V3 (ABC) V1 = atan(y(C) / x(C)) V2 = acos((Arm² + AC² - Arm²) / (2Arm AC)) Denne kan forenkles til: acos((AC² ) / (2Arm AC)) V3 = acos((Arm² + Arm² - AC²) / (2Arm Arm)) Denne kan forenkles til: acos((2Arm² - AC²) / (2Arm Arm))