Chapter 5: Problem 66
If \(270^{\circ}<\theta<360^{\circ}\), then which quadrant does \(\frac{\theta}{2}\) terminate in? a. \(\mathrm{QI}\) b. QII c. QIII d. QIV
Short Answer
Expert verified
The answer is b. QII.
Step by step solution
01
Identify the range of \( \theta \)
Given that \( 270^{\circ} < \theta < 360^{\circ} \). This means \( \theta \) is in the fourth quadrant. We need to determine the effects on \( \theta \) when divided by two.
02
Divide the inequality by 2
To find \( \frac{\theta}{2} \), divide the entire inequality by 2: \( \frac{270^{\circ}}{2} < \frac{\theta}{2} < \frac{360^{\circ}}{2} \). This simplifies to \( 135^{\circ} < \frac{\theta}{2} < 180^{\circ} \).
03
Determine quadrant based on \( \frac{\theta}{2} \) range
The range \( 135^{\circ} < \frac{\theta}{2} < 180^{\circ} \) falls within the second quadrant, which spans from \( 90^{\circ} \) to \( 180^{\circ} \).
04
Confirm which option matches the quadrant
The second quadrant is represented by option b, QII.
Unlock Step-by-Step Solutions & Ace Your Exams!
-
Full Textbook Solutions
Get detailed explanations and key concepts
-
Unlimited Al creation
Al flashcards, explanations, exams and more...
-
Ads-free access
To over 500 millions flashcards
-
Money-back guarantee
We refund you if you fail your exam.
Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Angle Measurement
In trigonometry, understanding angle measurement is a fundamental aspect. Angles can be measured in various ways, including degrees and radians. In this context, we focus on degrees.
- A full circle is composed of 360 degrees.
- Each quadrant of the circle is equal to 90 degrees.
- Angles are often defined in a range, such as \(0^{\circ} < \theta < 360^{\circ}\), to represent their possible locations on a coordinate plane.
Quadrants in Trigonometry
The coordinate plane is divided into four quadrants, each corresponding to a specific range of angles.
- **Quadrant I (QI):** This quadrant contains angles from \(0^{\circ}\) up to \(90^{\circ}\). Positive values for both sine and cosine functions are typical here.
- **Quadrant II (QII):** Angles from \(90^{\circ}\) to \(180^{\circ}\) are in the second quadrant. The sine function is positive, while the cosine function is negative.
- **Quadrant III (QIII):** This quadrant includes angles from \(180^{\circ}\) to \(270^{\circ}\). Here, both sine and cosine functions are negative.
- **Quadrant IV (QIV):** Finally, angles from \(270^{\circ}\) to \(360^{\circ}\) belong here. In this quadrant, cosine is positive, while sine is negative.
Inequality Solving
Solving inequalities is a foundational skill in mathematics, including trigonometry. Inequalities demonstrate a range of possible values that satisfy a particular condition. To illustrate:
- If you have an inequality, such as \(270^{\circ} < \theta < 360^{\circ}\), it implies that \(\theta\) lies within a specific segment of a circle.
- Solving inequalities can involve transforming or simplifying expressions while maintaining the inequality's truth. For example, in this exercise, dividing the entire inequality by 2 helps us understand where \(\frac{\theta}{2}\) terminates.