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Determine the coordinates of points on the unit circle where the tangent line is horizontal.

Answer 1

Abigail Nelson

Emma Johnson

To find the coordinates on the unit circle where the tangent line is horizontal, we first recall that the unit circle is defined by the equation:

$ x^2 + y^2 = 1 $

The slope of the tangent line to the circle at any point (x, y) is given by the derivative of y with respect to x. Differentiating implicitly, we get:

$ 2x + 2y \x0crac{dy}{dx} = 0 $

Solving for $\x0crac{dy}{dx}$, we find:

$ \x0crac{dy}{dx} = -\x0crac{x}{y} $

For the tangent line to be horizontal, the slope $\x0crac{dy}{dx}$ must be zero. This occurs when:

$ -\x0crac{x}{y} = 0 $

Thus, x must be zero. On the unit circle, the points with x = 0 are (0, 1) and (0, -1). Therefore, the coordinates are (0, 1) and (0, -1).

Answer 2

Alex Thompson

Christopher Garcia

To find the coordinates on the unit circle where the tangent line is horizontal, consider the unit circle equation:

$ x^2 + y^2 = 1 $

Differentiating implicitly, we get:

$ 2x + 2y x0crac{dy}{dx} = 0 $

Solving for $x0crac{dy}{dx}$ gives us:

$ x0crac{dy}{dx} = -x0crac{x}{y} $

For a horizontal tangent line, $x0crac{dy}{dx} = 0$, which implies x = 0. The solutions on the unit circle are (0, 1) and (0, -1).

Answer 3

Amelia Mitchell

Chloe Evans

For horizontal tangents, $x0crac{dy}{dx} = 0$. On the unit circle, this occurs at (0, 1) and (0, -1).