trig
posted by Sam .
find the math product of u and v
u= (6,7)
v= (3,9)

Could be a dot product (scalar product) or could be a vector product (cross product)
If a dot product then
6*3 + 7*9 = 45
If a cross product then
i j k
6 7 0
3 9 0 do determinant
k (6*9 (7*3) ) = k (54+21) = 75 in z direction