Problem 2

Question

In Exercises \(1-8,\) a point on the terminal side of angle \(\theta\) is given. Find the exact value of each of the six trigonometric functions of \(\theta\). $$(-12,5)$$

Step-by-Step Solution

Verified
Answer
The exact values of the six trigonometric functions for the given point (-12,5) are: \(sin\theta = \frac{5}{13}\), \(cos\theta = \frac{-12}{13}\), \(tan\theta = -\frac{5}{12}\), \(csc\theta = \frac{13}{5}\), \(sec\theta = -\frac{13}{12}\), \(cot\theta = -\frac{12}{5}\).
1Step 1: Find the Radius r
Compute the radius \(r\) using the Pythagorean theorem. The radius is given by the formula \(r = \sqrt{x^{2} + y^{2}}\), where \(x = -12\) and \(y = 5\). Hence, \(r = \sqrt{(-12)^{2} + 5^{2}} = \sqrt{144 + 25} = \sqrt{169} = 13\).
2Step 2: Calculate Sine
The sine function (\(sin\theta\)) is given by the ratio of the y-coordinate to the radius. So, \(sin\theta = \frac{y}{r} = \frac{5}{13}\).
3Step 3: Calculate Cosine
The cosine function (\(cos\theta\)) is given by the ratio of the x-coordinate to the radius. So, \(cos\theta = \frac{x}{r} = \frac{-12}{13}\).
4Step 4: Calculate Tangent
The tangent function (\(tan\theta\)) is given by the ratio of sine to cosine. So, \(tan\theta = \frac{sin\theta}{cos\theta} = \frac{5/13}{-12/13} = -\frac{5}{12}\).
5Step 5: Calculate Cosecant
The cosecant function (\(csc\theta\)) is the reciprocal of sine. So, \(csc\theta = \frac{1}{sin\theta} = \frac{13}{5}\).
6Step 6: Calculate Secant
The secant function (\(sec\theta\)) is the reciprocal of cosine. So, \(sec\theta = \frac{1}{cos\theta} = -\frac{13}{12}\).
7Step 7: Calculate Cotangent
The cotangent function (\(cot\theta\)) is the reciprocal of tangent. So, \(cot\theta = \frac{1}{tan\theta} = -\frac{12}{5}\).