Here's the pseudocode with inheritance: In C++, use the colon syntax for inheritance: class ForceVector : public Vector3D. This tells the compiler that ForceVector extends Vector3D and inherits all its members.
Call the parent constructor in the initializer list. You write ForceVector::ForceVector(double x, double y, double z) : Vector3D(x, y, z) { } .
The isZero() method is inherited from Vector3D .