Pythagorean theorem is a special case of the Law of Cosines and can be derived from it because the cosine of 90° is 0. It is best to find the angle opposite the longest side first. With the Law of Cosines, there is also no problem with obtuse angles as with the Law of Sines ...
// Once an object of tetgenio is declared, no array is created. One has to // // allocate enough memory for them. On the deletion of this object, the // // memory occupied by these arrays needs to be freed. The routine // // deinitialize() will be automatically called. It...