Determine the coordinates of a point on the unit circle where the tangent line has a slope of 3/4
To determine the coordinates of a point on the unit circle where the tangent line has a slope of $\frac{3}{4}$, we start with the equation of the unit circle:
$$x^2 + y^2 = 1$$
The slope of the tangent line at a point $(x, y)$ on the circle can be found by differentiating implicitly:
$$2x + 2y\frac{dy}{dx} = 0$$
Solving for $\frac{dy}{dx}$, we get:
$$\frac{dy}{dx} = -\frac{x}{y}$$
We need the slope to equal $\frac{3}{4}$:
$$-\frac{x}{y} = \frac{3}{4}$$
This implies:
$$y = -\frac{4x}{3}$$
Substitute $y = -\frac{4x}{3}$ back into the unit circle equation:
$$x^2 + \left(-\frac{4x}{3}\right)^2 = 1$$
$$x^2 + \frac{16x^2}{9} = 1$$
$$\frac{25x^2}{9} = 1$$
$$x^2 = \frac{9}{25}$$
$$x = \pm \frac{3}{5}$$
Substitute $x$ back into $y = -\frac{4x}{3}$:
$$y = \mp \frac{4 \cdot \frac{3}{5}}{3} = \mp \frac{4}{5}$$
The coordinates are:
$$\left(\frac{3}{5}, -\frac{4}{5}\right)$$ and $$\left(-\frac{3}{5}, \frac{4}{5}\right)$$