Answered

At Westonci.ca, we connect you with experts who provide detailed answers to your most pressing questions. Start exploring now! Experience the convenience of finding accurate answers to your questions from knowledgeable professionals on our platform. Our platform provides a seamless experience for finding reliable answers from a network of experienced professionals.

What are the exact values of the six trigonometric functions for [tex]\(-\frac{7\pi}{6}\)[/tex] radians?

Sagot :

To find the exact values of the six trigonometric functions for [tex]\(-\frac{7 \pi}{6}\)[/tex] radians, let's start by identifying in which quadrant this angle is located and using reference angles.

### Step 1: Identify the Location in the Unit Circle
The angle [tex]\(-\frac{7 \pi}{6}\)[/tex] radians can be understood by first considering the positive equivalent angle [tex]\(2 \pi - \frac{7 \pi}{6}\)[/tex], which simplifies to:

[tex]\[ 2 \pi - \frac{7 \pi}{6} = \frac{12 \pi}{6} - \frac{7 \pi}{6} = \frac{5 \pi}{6} \][/tex]

Since [tex]\( -\frac{7 \pi}{6}\)[/tex] radians is obtained by rotating [tex]\(\pi\)[/tex] radians plus an additional [tex]\(\frac{\pi}{6}\)[/tex] radians in the negative direction (clockwise), it places this angle in the second quadrant where sine is positive, and cosine and tangent are negative.

### Step 2: Determine the Reference Angle
The reference angle for [tex]\( -\frac{7 \pi}{6} \)[/tex] is derived by subtracting [tex]\(\pi\)[/tex]:
[tex]\[ -\frac{7 \pi}{6} + 2 \pi = -\frac{7 \pi}{6} + \frac{12 \pi}{6} = \frac{5 \pi}{6} \][/tex]

### Step 3: Compute the Trigonometric Functions
Now, we use the exact trigonometric value for [tex]\(\frac{\pi}{6}\)[/tex] to find:

1. Sine
[tex]\[ \sin\left(-\frac{7 \pi}{6}\right) = \sin\left(\frac{\pi}{6} + \pi\right) = - \sin\left(\frac{\pi}{6}\right) = -\frac{1}{2} \][/tex]

2. Cosine
[tex]\[ \cos\left(-\frac{7 \pi}{6}\right) = \cos\left(\frac{\pi}{6} + \pi\right) = - \cos\left(\frac{\pi}{6}\right)\][/tex]
[tex]\[ \cos\left(-\frac{7 \pi}{6}\right) = -\frac{\sqrt{3}}{2} \][/tex]

3. Tangent
[tex]\[ \tan\left(-\frac{7 \pi}{6}\right) = \tan\left(\frac{\pi}{6} + \pi\right) = \tan\left(\frac{\pi}{6}\right) \][/tex]
[tex]\[ \tan\left(-\frac{7 \pi}{6}\right) = -\frac{1}{\sqrt{3}} = -\frac{\sqrt{3}}{3} \][/tex]

4. Cosecant (reciprocal of sine)
[tex]\[ \csc\left(-\frac{7 \pi}{6}\right) = \frac{1}{\sin\left(-\frac{7 \pi}{6}\right)} = \frac{1}{- \frac{1}{2}} = -2 \][/tex]

5. Secant (reciprocal of cosine)
[tex]\[ \sec\left(-\frac{7 \pi}{6}\right) = \frac{1}{\cos\left(-\frac{7 \pi}{6}\right)} = \frac{1}{- \frac{\sqrt{3}}{2}} = -\frac{2}{\sqrt{3}} = -\frac{2\sqrt{3}}{3} \][/tex]

6. Cotangent (reciprocal of tangent)
[tex]\[ \cot\left(-\frac{7 \pi}{6}\right) = \frac{1}{\tan\left(-\frac{7 \pi}{6}\right)} = \frac{1}{- \frac{\sqrt{3}}{3}} = -\frac{3}{\sqrt{3}} = -\sqrt{3} \][/tex]

### Conclusion
The exact values of the six trigonometric functions for [tex]\(-\frac{7 \pi}{6}\)[/tex] radians are:
- [tex]\(\sin\left(-\frac{7 \pi}{6}\right) = 0.5\)[/tex]
- [tex]\(\cos\left(-\frac{7 \pi}{6}\right) = -0.8660254037844388\)[/tex]
- [tex]\(\tan\left(-\frac{7 \pi}{6}\right) = -0.5773502691896254\)[/tex]
- [tex]\(\csc\left(-\frac{7 \pi}{6}\right) = 2.0000000000000013\)[/tex]
- [tex]\(\sec\left(-\frac{7 \pi}{6}\right) = -1.1547005383792512\)[/tex]
- [tex]\(\cot\left(-\frac{7 \pi}{6}\right) = -1.7320508075688783\)[/tex]