Question
upstudy study bank question image url

Solve the equation \( 4 \cos x+2=3 \) for \( 0^{\circ} \leq x \leq 360^{\circ} \)

Ask by Delgado Gardner. in Kenya
Feb 03,2025

Real Tutor Solution

Tutor-Verified Answer

Answer

The solutions are approximately \( x \approx 75.52^{\circ} \) and \( x \approx 284.48^{\circ} \).

Solution

To solve the equation \( 4 \cos x + 2 = 3 \) for \( 0^{\circ} \leq x \leq 360^{\circ} \), follow these steps: ### Step 1: Isolate the Cosine Term Start by isolating the cosine term. \[ 4 \cos x + 2 = 3 \] Subtract 2 from both sides: \[ 4 \cos x = 1 \] Divide both sides by 4: \[ \cos x = \frac{1}{4} \] ### Step 2: Find the Principal Angle Find the principal angle whose cosine is \( \frac{1}{4} \). \[ x = \cos^{-1}\left(\frac{1}{4}\right) \] Using a calculator: \[ x \approx 75.52^{\circ} \] ### Step 3: Determine All Solutions in the Given Interval The cosine function is positive in the **first** and **fourth** quadrants. Therefore, there are two solutions within \( 0^{\circ} \leq x \leq 360^{\circ} \): 1. **First Quadrant:** \[ x \approx 75.52^{\circ} \] 2. **Fourth Quadrant:** \[ x = 360^{\circ} - 75.52^{\circ} = 284.48^{\circ} \] ### Final Answer The solutions to the equation \( 4 \cos x + 2 = 3 \) within the interval \( 0^{\circ} \leq x \leq 360^{\circ} \) are: \[ x \approx 75.52^{\circ} \quad \text{and} \quad x \approx 284.48^{\circ} \]

Reviewed and approved by the UpStudy tutoring team

error msg
Explain
Simplify this solution

Beyond the Answer

To solve the equation \( 4 \cos x + 2 = 3 \), we start by isolating the cosine term. 1. Subtract 2 from both sides: \[ 4 \cos x = 3 - 2 \] \[ 4 \cos x = 1 \] 2. Divide both sides by 4: \[ \cos x = \frac{1}{4} \] Now, we need to find the angles \( x \) in the range \( 0^{\circ} \leq x \leq 360^{\circ} \) where the cosine value is \( \frac{1}{4} \). 3. Using a calculator or inverse cosine function: \[ x = \cos^{-1}\left(\frac{1}{4}\right) \approx 75.5^{\circ} \] Since the cosine function is positive in both the first and fourth quadrants, we find the second solution by subtracting \( 75.5^{\circ} \) from \( 360^{\circ} \): 4. Find the second angle: \[ x_2 = 360^{\circ} - 75.5^{\circ} \approx 284.5^{\circ} \] Thus, the solutions to the equation \( 4 \cos x + 2 = 3 \) within the interval \( 0^{\circ} \leq x \leq 360^{\circ} \) are approximately: \[ x \approx 75.5^{\circ} \quad \text{and} \quad x \approx 284.5^{\circ} \]

Related Questions

Latest Trigonometry Questions

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