- #1
Did I Make a Mistake in my Coordinates? Help Needed!
- Context: Undergrad
- Thread starter Shafia Zahin
- Start date
-
- Tags
- Confusion Coordinates
Click For Summary
Discussion Overview
The discussion revolves around the labeling of coordinates in a diagram, specifically whether the coordinates of point B should be (a cos theta, a sin theta) or (-a cos theta, a sin theta). The scope includes conceptual clarification and technical reasoning related to coordinate systems and trigonometric functions.
Discussion Character
- Conceptual clarification, Technical explanation, Debate/contested
Main Points Raised
- One participant questions the labeling of coordinates, suggesting that point B should be (-a cos theta, a sin theta) instead of (a cos theta, a sin theta).
- Another participant asserts that there is nothing wrong with the labeling, explaining that cos theta is negative in the second and third quadrants.
- A subsequent reply reiterates the previous point about the labeling being correct but acknowledges confusion regarding the derivation presented in the attachment.
- Another participant critiques the triangle construction in the diagram, noting that the x-coordinate should reflect its position relative to the origin, suggesting it should be negative based on the derivation.
- A later reply indicates understanding after the clarification, expressing gratitude for the explanation.
Areas of Agreement / Disagreement
Participants express differing views on the correctness of the coordinate labeling, with some asserting it is accurate and others suggesting it may be incorrect based on the context of the diagram.
Contextual Notes
The discussion highlights potential limitations in understanding the coordinate system and the assumptions made regarding the origin's position and the treatment of lengths in the triangle construction.
- #2
Fightfish
- 953
- 118
No there is nothing wrong with the labeling of the coordinates in the diagram. Recall that ##\cos \theta## is negative for ##\pi/2 < \theta < 3\pi/2## (or what you may know as the second and third quadrants).
- #3
- #4
Fightfish
- 953
- 118
When you did the triangle construction in your diagram, you treated ##x## there as a length, which only takes on positive values, but ignored its position relative to where the origin was defined. So, the x-coordinate of the point should in fact be the negative of the ##x## in your derivation.
- #5
Shafia Zahin
- 31
- 1
Oh,now I got it,thank you so muchFightfish said:
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