Good afternoon Dr. Taylor,
I have a question regarding Problem 2 on the Section 10.2 homework. The question asks me to find a 3D unit vector in the same direction as the 3D vector a = <5,2,-1>. I went through the motions for finding a unit vector (first finding the length with the Pythagorean theorem, then dividing each vector component by the length) and got 0.913i+0.365j-0.183k as my unit vector in the same direction. I double checked the length to make sure it was 1 by doing Pythag again, and the length was 1. However, WeBWorK is saying that I'm wrong, and after a bit of Googling to find similar problems, it looks like I have done the work correctly. My question is, why am I wrong?
Thank you, and sorry if this email is a little long-winded for a single question.
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No apologies necessary, you did exactly what you should do. It looks to me like you have the right answer, so I'm not sure what the problem with webwork is. There is a little button down at the bottom of the page that says "Email Instructor"; if you click on that it will send me a copy of your webwork page and I can usually spot what is going wrong.
