Question
upstudy study bank question image url

5. Determine the exact value for the following: (5 marks) \[ \sin \frac{11 \pi}{6} \sec \frac{2 \pi}{3}+\tan \frac{5 \pi}{4} \]

Ask by Norton Chandler. in Canada
Jan 24,2025

Real Tutor Solution

Tutor-Verified Answer

Answer

The exact value of the expression is 2.

Solution

To determine the exact value of the expression: \[ \sin \frac{11\pi}{6} \sec \frac{2\pi}{3} + \tan \frac{5\pi}{4} \] we will evaluate each trigonometric function separately. 1. **Evaluating \(\sin \frac{11\pi}{6}\):** - The angle \(\frac{11\pi}{6}\) is in the **4th quadrant** where sine is negative. - The reference angle is \(2\pi - \frac{11\pi}{6} = \frac{\pi}{6}\). - \(\sin \frac{\pi}{6} = \frac{1}{2}\), so: \[ \sin \frac{11\pi}{6} = -\frac{1}{2} \] 2. **Evaluating \(\sec \frac{2\pi}{3}\):** - Recall that \(\sec \theta = \frac{1}{\cos \theta}\). - The angle \(\frac{2\pi}{3}\) is in the **2nd quadrant** where cosine is negative. - The reference angle is \(\pi - \frac{2\pi}{3} = \frac{\pi}{3}\). - \(\cos \frac{\pi}{3} = \frac{1}{2}\), so: \[ \cos \frac{2\pi}{3} = -\frac{1}{2} \] \[ \sec \frac{2\pi}{3} = \frac{1}{\cos \frac{2\pi}{3}} = \frac{1}{-\frac{1}{2}} = -2 \] 3. **Evaluating \(\tan \frac{5\pi}{4}\):** - The angle \(\frac{5\pi}{4}\) is in the **3rd quadrant** where tangent is positive. - The reference angle is \(\frac{5\pi}{4} - \pi = \frac{\pi}{4}\). - \(\tan \frac{\pi}{4} = 1\), so: \[ \tan \frac{5\pi}{4} = 1 \] 4. **Combining the results:** \[ \sin \frac{11\pi}{6} \cdot \sec \frac{2\pi}{3} + \tan \frac{5\pi}{4} = \left(-\frac{1}{2}\right) \cdot (-2) + 1 = 1 + 1 = 2 \] **Final Answer:** \[ 2 \]

Reviewed and approved by the UpStudy tutoring team

error msg
Explain
Simplify this solution

Beyond the Answer

To solve \( \sin \frac{11 \pi}{6} \sec \frac{2 \pi}{3}+\tan \frac{5 \pi}{4} \), we first calculate each trigonometric function step by step. 1. **Calculate \( \sin \frac{11 \pi}{6} \)**: \[ \sin \frac{11 \pi}{6} = -\frac{1}{2} \quad (\text{since it's in the fourth quadrant}) \] 2. **Calculate \( \sec \frac{2 \pi}{3} \)**: \[ \sec \theta = \frac{1}{\cos \theta} \] Since \( \frac{2 \pi}{3} \) is in the second quadrant, we have: \[ \cos \frac{2 \pi}{3} = -\frac{1}{2} \implies \sec \frac{2 \pi}{3} = -2 \] 3. **Now, substitute into the expression for \( \sin \frac{11 \pi}{6} \sec \frac{2 \pi}{3} \)**: \[ \sin \frac{11 \pi}{6} \sec \frac{2 \pi}{3} = \left(-\frac{1}{2}\right)(-2) = 1 \] 4. **Calculate \( \tan \frac{5 \pi}{4} \)**: \[ \tan \frac{5 \pi}{4} = 1 \quad (\text{since } \tan \theta = \frac{\sin \theta}{\cos \theta} \text{ and both sine and cosine are negative in the third quadrant}) \] 5. **Add the two results together**: \[ \sin \frac{11 \pi}{6} \sec \frac{2 \pi}{3} + \tan \frac{5 \pi}{4} = 1 + 1 = 2 \] Thus, the final result is: \[ \boxed{2} \]

Try Premium now!
Try Premium and ask Thoth AI unlimited math questions now!
Maybe later Go Premium
Study can be a real struggle
Why not UpStudy it?
Select your plan below
Premium

You can enjoy

Start now
  • Step-by-step explanations
  • 24/7 expert live tutors
  • Unlimited number of questions
  • No interruptions
  • Full access to Answer and Solution
  • Full Access to PDF Chat, UpStudy Chat, Browsing Chat
Basic

Totally free but limited

  • Limited Solution
Welcome to UpStudy!
Please sign in to continue the Thoth AI Chat journey
Continue with Email
Or continue with
By clicking “Sign in”, you agree to our Terms of Use & Privacy Policy