Question

If a=10, b =13 and the angle between a and b is 59.5 degree, what is the scalar product of a and b

Answer 1

Given that $a=10,b=13, \theta=59.5\degree.$

Scalar product

$$\bm{a}\cdot\bm{b}=ab\cos{\theta}$$ $$\bm{a}\cdot\bm{b}=10 \cdot13\cdot\cos{59.5\degree}\approx65.98$$