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$Calculate Cosine Using Unit Circle in the Complex Plane$

Answer 1

Abigail Nelson

Benjamin Clark

Consider a point on the unit circle in the complex plane, given by the complex number $z = e^{i\theta}$ where $\theta$ is the angle in radians from the positive x-axis.

The coordinate of this point can be written as $(\cos\theta, \sin\theta)$.

If $\theta = \frac{\pi}{4}$, find the cosine of $\theta$.

Since $\theta = \frac{\pi}{4}$, we can substitute into the formula:

$\cos\left( \frac{\pi}{4} \right) = \frac{\sqrt{2}}{2}$

Answer 2

Alex Thompson

Ava Martin

Consider a point on the unit circle in the complex plane, given by the complex number $z = e^{i heta}$ where $ heta$ is the angle in radians from the positive x-axis.

The coordinate of this point can be written as $(cos heta, sin heta)$.

If $ heta = frac{pi}{6}$, find the cosine of $ heta$.

Since $ heta = frac{pi}{6}$, we can substitute into the formula:

$cosleft( frac{pi}{6}
ight) = frac{sqrt{3}}{2}$

Answer 3

Amelia Mitchell

Emma Johnson

Consider a point on the unit circle in the complex plane, given by the complex number $z = e^{i heta}$ where $ heta$ is the angle in radians from the positive x-axis.

The coordinate of this point can be written as $(cos heta, sin heta)$.

If $ heta = frac{pi}{3}$, find the cosine of $ heta$.

Since $ heta = frac{pi}{3}$, we can substitute into the formula:

$cosleft( frac{pi}{3}
ight) = frac{1}{2}$