Questions: Let (8,6) be a point on the terminal side of θ.
Find the exact values of cos θ, sec θ, and cot θ.
cos θ =□
sec θ =□
cot θ =□
Transcript text: Let $(8,6)$ be a point on the terminal side of $\theta$.
Find the exact values of $\cos \theta, \sec \theta$, and $\cot \theta$.
\[
\begin{aligned}
\cos \theta & =\square \\
\sec \theta & =\square \\
\cot \theta & =\square
\end{aligned}
\]
Solution
Solution Steps
To find the trigonometric values for the given point \((8,6)\) on the terminal side of \(\theta\), we need to:
Calculate the hypotenuse \(r\) using the Pythagorean theorem.
Use the definitions of cosine, secant, and cotangent to find the required values.
Step 1: Calculate the Hypotenuse
Given the point \((8, 6)\), we can find the hypotenuse \(r\) using the Pythagorean theorem:
\[
r = \sqrt{x^2 + y^2} = \sqrt{8^2 + 6^2} = \sqrt{64 + 36} = \sqrt{100} = 10.
\]
Step 2: Calculate \(\cos \theta\)
Using the definition of cosine:
\[
\cos \theta = \frac{x}{r} = \frac{8}{10} = 0.8.
\]
Step 3: Calculate \(\sec \theta\)
The secant is the reciprocal of cosine:
\[
\sec \theta = \frac{1}{\cos \theta} = \frac{1}{0.8} = 1.25.
\]
Step 4: Calculate \(\cot \theta\)
Using the definition of cotangent:
\[
\cot \theta = \frac{x}{y} = \frac{8}{6} = \frac{4}{3} \approx 1.3333.
\]