[TYPO] Forgotten negative sign

[SheepTester]

https://github.com/anematode/gatm/blob/ad494de39068d117cceabdcdd52f16fb54f65699/comp_map/comp_map_answers.tex#L761

Equation has -cos theta in the second row, second column, but the corresponding cell in the other matrix is positive.

Also, why are the matrix brackets round? lol

[SheepTester]

Since I'm here, here's some other comments I'm not sure if they deserve an issue:

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https://github.com/anematode/gatm/blob/ad494de39068d117cceabdcdd52f16fb54f65699/comp_map/comp_map_answers.tex#L650

I disagree here since I think stretches imply a positive stretch factor, so they can't be used to reflect. Especially since here

https://github.com/anematode/gatm/blob/master/comp_map/comp_map_answers.tex#L1054-L1058

says that reflections are necessary to flip orientation.

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https://github.com/anematode/gatm/blob/ad494de39068d117cceabdcdd52f16fb54f65699/comp_map/comp_map_answers.tex#L1096-L1133

I don't think "scale" is a good word to use here because "scale" could be "dilate" or "stretch," but even a stretch in the direction of <c, d> would change the <a, b> vector I think. Perhaps the <c, d> vector could get scaled, or the parallelogram gets l e n g t h e n e d

[ytchang05]

The negative sign has been un-dropped in 9f10b9e222fa832e1bc9a7e451af1cb9c59b58aa, the other comments in this issue I will leave to @anematode .

[anematode]

anematode

[SheepTester]

/cc @heaucques