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What Does $sin$ Represent on the Unit Circle?

Answer 1

Abigail Nelson

Abigail Nelson

On the unit circle, the function $\sin$ represents the y-coordinate of a point on the circle. The unit circle is defined as a circle with a radius of 1, centered at the origin of the coordinate system.

First, consider a point on the unit circle defined by an angle $\theta$, measured in radians from the positive x-axis. This point can be represented as $(\cos(\theta), \sin(\theta))$.

Because the radius of the unit circle is 1, the coordinates $(\cos(\theta), \sin(\theta))$ correspond to the horizontal and vertical distances from the origin.

Therefore,

$\sin(\theta)$

represents the vertical distance from the x-axis to the point on the unit circle. For example, if $\theta = \frac{\pi}{6}$ (30 degrees), the point on the unit circle is $(\frac{\sqrt{3}}{2}, \frac{1}{2})$. Thus, $\sin\left(\frac{\pi}{6}\right) = \frac{1}{2}$.

Answer 2

Alex Thompson

Ava Martin

In the context of the unit circle, where the circle has a radius of 1 and is centered at the origin $(0,0)$, $sin$ represents the y-coordinate of a point on the circle with a given angle $ heta$. The angle $ heta$ is measured counterclockwise from the positive x-axis.

To locate a point on the unit circle corresponding to the angle $ heta$, we use the coordinates $(cos( heta), sin( heta))$.

Since the radius of the circle is 1, the coordinates $(cos( heta), sin( heta))$ provide the exact position of the point on the unit circle.

Thus,

$sin( heta)$

is the y-coordinate of the point. For instance, at $ heta = frac{pi}{4}$ (45 degrees), the point on the unit circle is $(frac{sqrt{2}}{2}, frac{sqrt{2}}{2})$, meaning $sinleft(frac{pi}{4}
ight) = frac{sqrt{2}}{2}$.

Answer 3

Amelia Mitchell

Henry Green

In the unit circle, $sin$ corresponds to the y-coordinate of a point at angle $ heta$. The unit circle is a circle with a radius of 1 centered at the origin.

For a given angle $ heta$, the coordinates of the point are $(cos( heta), sin( heta))$.

Therefore,

$sin( heta)$

is the y-coordinate of this point. For example, for $ heta = frac{pi}{3}$, $sinleft(frac{pi}{3}
ight) = frac{sqrt{3}}{2}$.