Question 15

1. If a = 6i – 5j, b = 2i + 7j and c = 8i+ 2j, find the values of the scalars, x and y such that c = xa + yb.
2. The vectors a and b are such that |a| = 3 cm, |b| = 10 cm and |a + b| = √139. Find:

1. the angle between a and b;
2. the scalar (dot) product of a and b.