posted by Wykeena .
The problem concern the position vectors r1=2.43mi-4.74mj and r2=-3.02mi+0.85mj.
Find the angle between the two vectors. Hint: Find the angle each makes with the +x-axis.
do the dot product, and the magnitude of the cross product.
cross product= r1XR2=magR1*magR2*sinTheta
dot product= magR1*magR2*cosTheta
cross product/dot product = tan theta
solve for theta.
How do you get cross product?
= 2.31iX(3.02i+.85j) + (-4.74j)X(3.02i+.85j)
well iXi=0, iXj= k, jXi=-k, jXj=0
or = 2.31*.85k+4.74*3.02k=CCCCc
How do you get the dot product?
so tan theta = CCCCC/DDDDDD
I see I missed a sign on R2, correct that please.