From 77e7956b788189ab1dd44812f0396a31031470f3 Mon Sep 17 00:00:00 2001 From: z3rOR0ne Date: Sat, 26 Apr 2025 07:02:21 -0700 Subject: [PATCH] :memo: Made note of unit circle values --- mathematics/unit_circle_trig_tables.md | 58 ++++++++++++++++++++++++++ 1 file changed, 58 insertions(+) create mode 100644 mathematics/unit_circle_trig_tables.md diff --git a/mathematics/unit_circle_trig_tables.md b/mathematics/unit_circle_trig_tables.md new file mode 100644 index 00000000..81f84432 --- /dev/null +++ b/mathematics/unit_circle_trig_tables.md @@ -0,0 +1,58 @@ +# Unit Circle Trigonometric Values + +## Key Angles in Degrees and Radians: + +- $0^\circ = 0$ radians +- $30^\circ = \frac{\pi}{6}$ radians +- $45^\circ = \frac{\pi}{4}$ radians +- $60^\circ = \frac{\pi}{3}$ radians +- $90^\circ = \frac{\pi}{2}$ radians +- $120^\circ = \frac{2\pi}{3}$ radians +- $135^\circ = \frac{3\pi}{4}$ radians +- $150^\circ = \frac{5\pi}{6}$ radians +- $180^\circ = \pi$ radians +- $210^\circ = \frac{7\pi}{6}$ radians +- $225^\circ = \frac{5\pi}{4}$ radians +- $240^\circ = \frac{4\pi}{3}$ radians +- $270^\circ = \frac{3\pi}{2}$ radians +- $300^\circ = \frac{5\pi}{3}$ radians +- $315^\circ = \frac{7\pi}{4}$ radians +- $330^\circ = \frac{11\pi}{6}$ radians +- $360^\circ = 2\pi$ radians + +## Trigonometric Values at Key Angles: + +| Angle (Degrees) | Angle (Radians) | $ \cos(\theta) $ | $ \sin(\theta) $ | $ \tan(\theta) $ | +| --------------- | ----------------- | --------------------- | --------------------- | --------------------- | +| $0^\circ$ | $0$ | $1$ | $0$ | $0$ | +| $30^\circ$ | $\frac{\pi}{6}$ | $\frac{\sqrt{3}}{2}$ | $\frac{1}{2}$ | $\frac{1}{\sqrt{3}}$ | +| $45^\circ$ | $\frac{\pi}{4}$ | $\frac{\sqrt{2}}{2}$ | $\frac{\sqrt{2}}{2}$ | $1$ | +| $60^\circ$ | $\frac{\pi}{3}$ | $\frac{1}{2}$ | $\frac{\sqrt{3}}{2}$ | $\sqrt{3}$ | +| $90^\circ$ | $\frac{\pi}{2}$ | $0$ | $1$ | $\text{undefined}$ | +| $120^\circ$ | $\frac{2\pi}{3}$ | $-\frac{1}{2}$ | $\frac{\sqrt{3}}{2}$ | $-\sqrt{3}$ | +| $135^\circ$ | $\frac{3\pi}{4}$ | $-\frac{\sqrt{2}}{2}$ | $\frac{\sqrt{2}}{2}$ | $-1$ | +| $150^\circ$ | $\frac{5\pi}{6}$ | $-\frac{\sqrt{3}}{2}$ | $\frac{1}{2}$ | $-\frac{1}{\sqrt{3}}$ | +| $180^\circ$ | $\pi$ | $-1$ | $0$ | $0$ | +| $210^\circ$ | $\frac{7\pi}{6}$ | $-\frac{\sqrt{3}}{2}$ | $-\frac{1}{2}$ | $\frac{1}{\sqrt{3}}$ | +| $225^\circ$ | $\frac{5\pi}{4}$ | $-\frac{\sqrt{2}}{2}$ | $-\frac{\sqrt{2}}{2}$ | $1$ | +| $240^\circ$ | $\frac{4\pi}{3}$ | $-\frac{1}{2}$ | $-\frac{\sqrt{3}}{2}$ | $\sqrt{3}$ | +| $270^\circ$ | $\frac{3\pi}{2}$ | $0$ | $-1$ | $\text{undefined}$ | +| $300^\circ$ | $\frac{5\pi}{3}$ | $\frac{1}{2}$ | $-\frac{\sqrt{3}}{2}$ | $-\sqrt{3}$ | +| $315^\circ$ | $\frac{7\pi}{4}$ | $\frac{\sqrt{2}}{2}$ | $-\frac{\sqrt{2}}{2}$ | $-1$ | +| $330^\circ$ | $\frac{11\pi}{6}$ | $\frac{\sqrt{3}}{2}$ | $-\frac{1}{2}$ | $\frac{1}{\sqrt{3}}$ | +| $360^\circ$ | $2\pi$ | $1$ | $0$ | $0$ | + +## Patterns to Notice: + +1. **Sine and Cosine Symmetry:** + - The values of sine and cosine are symmetric in different quadrants. + - For example, sine values are positive in the first and second quadrants, + negative in the third and fourth quadrants. + - Cosine values are positive in the first and fourth quadrants, negative in + the second and third quadrants. + +2. **Tangent Behavior:** + - Tangent values are undefined when cosine equals zero (at $90^\circ$ and + $270^\circ$). + - Tangent has a period of $180^\circ$, so the values for angles like + $45^\circ$ and $225^\circ$ are the same.