this post was submitted on 07 May 2024
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  • Show that arcsin y = arccos x is the equation of a circle.
  • Note that the equation of a circle is x^2+y^2=1.
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[–] [email protected] 4 points 4 months ago (1 children)

The text below the image is wrong. It should state arcsin(y) = arccos(x)

[–] [email protected] 3 points 4 months ago

mb, its now fixed

[–] [email protected] 4 points 4 months ago

solutionarcsin(y) = arccos(x) implies y = sin(arccos(x))

sin(arccos(x)) can be shown to equal ±sqrt(1-x²) with a simple triangle diagram and the pythagorean theorem, so we have y = ±sqrt(1-x²). This can be easily re-arranged to give x² + y² = 1.

[–] [email protected] 3 points 4 months ago* (last edited 4 months ago)
[–] [email protected] 2 points 4 months ago

::: spoiler spoiler

sin^2 (x) + cos^2 (x) = 1