No idea what the textbook is doing

AI Thread Summary
The textbook's solution appears to be incorrect due to discrepancies in the problem statement, specifically the length of the rod being stated as 6m instead of 4m. Additionally, the use of the sine function is questioned because the hypotenuse of the triangles is not defined or labeled. The correct approach should involve using the tangent function instead. The calculations presented by the user yield a different value for x, indicating a potential error in the textbook's methodology. Overall, the discussion highlights significant flaws in the textbook's problem-solving approach.
phospho
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I mean, I used a similar method as they're using, but I didn't get their answer at all. Where did the x-4 come from? (I used x-6), also, I got d = (6-x)tan50 and d = xtan(3) solving this to get x = 4.04
 

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phospho said:
I mean, I used a similar method as they're using, but I didn't get their answer at all. Where did the x-4 come from? (I used x-6), also, I got d = (6-x)tan50 and d = xtan(3) solving this to get x = 4.04

Looks like the book's solution is incorrect on two counts. First, the problem statement has changed at some point to have 6m as the length of the rod, while the solution assumes it's 4m. Second, I don't see how they can use the sine function since the hypotenuse's of the triangles are unknown (and not even labelled). They should use the tan function.
 
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