A force of magnitude 15 N is the resultant of two forces, one of which has a magnitude of 8 N and acts at an angle of 30 to the resultant. Find the magnitude and direction of the other force. 6marks If vector Vector a = (3, 2, 9), and Vector b = (-4, 7, 2), find axb 4marks Verify (a+b)x(a+b)=0. What can be said about two vectors whose cross-product is the zero vector?4marks a. Explain why the cross product does not exist in 2-space. b. How could you do a cross-product with two-dimensional vectors? Prove the identity +12 + | | = 22+2712