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Prove that the sum of the squares of the $sin$ and $cos$ functions on the unit circle equals 1.

Answer 1

Abigail Nelson

Samuel Scott

On the unit circle, any point is represented as $(\cos(\theta), \sin(\theta))$, where $\theta$ is the angle formed with the positive x-axis.

According to the Pythagorean theorem, the equation of the unit circle is:

$ x^2 + y^2 = 1 $

Substituting the coordinates:

$ \cos^2(\theta) + \sin^2(\theta) = 1 $

Therefore, the sum of the squares of the sine and cosine functions on the unit circle equals 1.

Answer 2

Alex Thompson

Chloe Evans

The unit circle is defined by the equation:

$ x^2 + y^2 = 1 $

For any point on the unit circle at an angle $ heta$, the coordinates are given by:

$ x = cos( heta) $

$ y = sin( heta) $

Substituting these into the unit circle equation gives:

$ cos^2( heta) + sin^2( heta) = 1 $

Answer 3

Amelia Mitchell

Benjamin Clark

On the unit circle:

$ cos^2( heta) + sin^2( heta) = 1 $