Question

In the problems for session 38, how is the gradient of T = <1,2,2> rather than <2,4,4>?

Answer 1

If all you want is the direction of the gradient, you can factor out any common value. (or, often it's nice to normalize the gradient vector to unit length )

However, they make a mistake by not using <2,4,4> to calculate the actual change in w as you move a specific distance and direction. For this problem, you must use the correct magnitude and direction of the gradient.