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WebWork 1, Problem 1

audrey

I’m already stumped on the first problem of the first WebWork assignment! The problem asks me to find a formula for the distance from the point (a,b,c) to the z-axis. I know the distance formula, so I input

\sqrt{a^2+b^2+c^2}.

That’s marked incorrect but I’m not sure why. Any idea why?

Samwise

I know this is an example question, but I actually had the same issue, so I’m posting a response in case anyone else is having a similar struggle. The problem is that you’re taking the z-axis into account when it should be equal to 0, so plug 0 in for your C-coordinate and that should help.