College Physics 10th Edition by Raymond Serway,Chris Vuille

Exercise 46

Spaceship A moves away from Earth at a speed of 0.800 c (Fig. P26.19). Spaceship B pursues at a speed of 0.900 c relative to Earth. Observers on Earth see B overtaking A at a relative speed of 0.100 c. With what speed is B overtaking A as seen by the crew of spaceship B