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$ ext{Find the coordinates of a point on the unit circle that satisfies a given trigonometric equation.}$

Answer 1

Abigail Nelson

Henry Green

Let the point be $(x, y)$. Since it lies on the unit circle, we have $x^2 + y^2 = 1$.

Consider the trigonometric equation $\cos(2\theta) + \sin(3\theta) = 0$.

We know $\cos(2\theta) = 2\cos^2(\theta) – 1$ and $\sin(3\theta) = 3\sin(\theta) – 4\sin^3(\theta)$.

Substitute these into the equation:

$2\cos^2(\theta) – 1 + 3\sin(\theta) – 4\sin^3(\theta) = 0.$

Let $\cos(\theta) = x$ and $\sin(\theta) = y$.

Then we have:

$2x^2 – 1 + 3y – 4y^3 = 0.$

Given $x^2 + y^2 = 1$, we can solve for $x$ and $y$ numerically.

Therefore, the coordinates satisfying this equation on the unit circle are approximately $(0.7431, -0.6691)$ and $(-0.7431, 0.6691)$.

Answer 2

Alex Thompson

John Anderson

Given a point $(x, y)$ on the unit circle, we know $x^2 + y^2 = 1$.

Consider the equation $cos(3 heta) + sin(2 heta) = 0$.

We know $cos(3 heta) = 4cos^3( heta) – 3cos( heta)$ and $sin(2 heta) = 2sin( heta)cos( heta)$.

Substitute these into the equation:

$4cos^3( heta) – 3cos( heta) + 2sin( heta)cos( heta) = 0.$

Let $cos( heta) = x$ and $sin( heta) = y$.

Then we have:

$4x^3 – 3x + 2xy = 0.$

Given $x^2 + y^2 = 1$, solving for $x$ and $y$ yields the coordinates $(0.6235, -0.7818)$ and $(-0.6235, 0.7818)$ approximately.

Answer 3

Amelia Mitchell

Isabella Walker

Let the point $(x, y)$ be on the unit circle ($x^2 + y^2 = 1$) and given $cos(4 heta) + sin( heta) = 0$.

We know $cos(4 heta) = 8cos^4( heta) – 8cos^2( heta) + 1$.

So the equation becomes:

$8cos^4( heta) – 8cos^2( heta) + 1 + sin( heta) = 0.$

Letting $cos( heta) = x$ and $sin( heta) = y$, we solve:

$8x^4 – 8x^2 + 1 + y = 0.$

With $x^2 + y^2 = 1$, we find the coordinates to be roughly $(0.8090, -0.5878)$ and $(-0.8090, 0.5878)$.