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Ch. 1 - Angles and the Trigonometric Functions
Blitzer - Trigonometry 3rd Edition
Blitzer3rd EditionTrigonometryISBN: 9780137316601Not the one you use?Change textbook
Chapter 1, Problem 43

In Exercises 41–56, use the circle shown in the rectangular coordinate system to draw each angle in standard position. State the quadrant in which the angle lies. When an angle's measure is given in radians, work the exercise without converting to degrees.
Circle in rectangular coordinates for measuring angles in standard position.
3πœ‹/4

Verified step by step guidance
1
Understand that the angle is given in radians and is in standard position, meaning its vertex is at the origin and the initial side lies along the positive x-axis.
Recall that one full revolution around the circle corresponds to \(2\pi\) radians, and the circle is divided into four quadrants, each spanning \(\frac{\pi}{2}\) radians.
Locate the angle \(\frac{3\pi}{4}\) on the circle by starting from the positive x-axis and moving counterclockwise \(\frac{3\pi}{4}\) radians.
Since \(\frac{3\pi}{4}\) is greater than \(\frac{\pi}{2}\) but less than \(\pi\), the terminal side of the angle lies in the second quadrant.
Draw the angle on the circle by marking the terminal side at \(\frac{3\pi}{4}\) radians, which is halfway between \(\frac{\pi}{2}\) and \(\pi\), and label the quadrant as the second quadrant.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Angles in Standard Position

An angle is in standard position when its vertex is at the origin of the coordinate system, and its initial side lies along the positive x-axis. The angle is measured by rotating the terminal side from the initial side, counterclockwise for positive angles and clockwise for negative angles.
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Drawing Angles in Standard Position

Radian Measure and the Unit Circle

Radian measure relates the length of an arc on the unit circle to the radius. One full revolution around the circle equals 2Ο€ radians. Angles can be expressed in radians without converting to degrees, which simplifies calculations involving the unit circle.
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Introduction to the Unit Circle

Quadrants of the Coordinate Plane

The coordinate plane is divided into four quadrants, numbered counterclockwise starting from the upper right. The quadrant in which the terminal side of an angle lies determines the sign of the sine and cosine values and helps in identifying the angle's position.
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Quadratic Formula