Vector 1 points along the z axis and has magnitude V1 = 80. Vector 2 lies in the xz plane, has magnitude V2 = 50, and makes a -37° angle with the x axis (points below the x axis). What is the scalar product V1·V2?

.  = 2574.08    

Explanation:

given data

magnitude V1 = 80

magnitude V2 = 50

angle a =  -37°

solution

= 80 k

= 50 cos{37} i  - 50sin{37} k

so that here .    is

.  = 80 k . ( 50 cos{37} i  - 50sin{37} k )

.  = 80 k . (  38.270 i + 32.176 k )

.  = 2574.08    

if they have a finite resultant