Question

If a = [1,2,3] and b = [1, 3, –2], find the angle between a and b.

Answer 1

85.9°

Explanation:

angle =
`\arccos(a\cdot b)/(|a| |b|) = \arccos\frac{1+6-6}{{√(1+4+9)}√(1+9+4)}\\=\arccos(1)/(14)=85.9 degrees`