Wikipedia:Reference desk/Archives/Mathematics/2018 February 12

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February 12

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Statics problem

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I figured out the resultant force from the three component forces at [1] but part B stumps me. It seems obvious to me that the answer should be the 2.45, but that's marked wrong when I entered it in part b. What else could the answer be? Imagine Reason (talk) 12:57, 12 February 2018 (UTC)[reply]

The problem seems poorly worded since it says "to be added" without saying what it's to be added to. So are you sure that T is meant to be added to R? Also, without seeing the whole problem it's hard to know if the value of R is correct; you're implying that the it was scored as correct but erroneous answer keys have been known. As a general principle, if u and v are perpendicular, then the value of t which minimizes |u+v+tu| is -1. --RDBury (talk) 16:20, 12 February 2018 (UTC)[reply]