# Activities to Teach Students Trigonometric Ratios: Find an Angle Measure

Trigonometry is an important branch of mathematics that deals with angles and their relationships with sides of triangles. A good understanding of trigonometry is crucial for students who wish to pursue a career in fields such as science and engineering. Teaching trigonometric ratios and angles can be challenging for educators, especially when they have to make abstract concepts more tangible and relatable to students. However, with the right activities and strategies, learning trigonometry can be enjoyable and engaging. In this article, we will discuss activities to teach students trigonometric ratios, specifically how to find an angle measure.

Activity 1: The Unit Circle

The unit circle is a common visual tool used in trigonometry. It is a circle with a radius of one unit, centered at the origin of a coordinate plane. Using the unit circle, we can define the six trigonometric ratios, sine, cosine, tangent, cosecant, secant, and cotangent. To introduce the idea of the unit circle, have students draw a circle on graph paper and label the x and y-axis. Then, have them plot points along the circle at various degrees (e.g., 0°, 30°, 45°, 60°, 90°, 180°, 270°, 360°). Next, have them label the coordinates of each point and introduce the terms sine, cosine, and tangent ratios, using SOHCAHTOA.

Activity 2: Trig Functions on the Calculator

Most calculators come with built-in trigonometric functions, which allow users to input a degree or radian measure and get the corresponding trigonometric ratio. Teach students how to use these functions on their calculators and have them practice calculating trigonometric ratios for various angle measures. This activity can be done individually or in pairs and can be used as an assessment tool for teachers to gauge students’ understanding.

Activity 3: Angle Estimation

This activity is an excellent way to help students estimate angle measures without using a calculator. Have students draw a right triangle on graph paper with one known side length and an unknown acute angle. Then, ask them to estimate the angle measure using visual cues and knowledge of angles. Afterward, have them use the SOHCAHTOA method to find the exact measure of the angle. Repeat this activity a few times with different triangle dimensions to help students hone their estimation skills.

Activity 4: Finding an Angle Measure in Context

It is essential that students understand how trigonometry applies to real-world scenarios. Create real-world problems that require students to use trigonometric ratios to find an angle measure. For instance, a bridge engineer might need to calculate the angle measure required to place a steel beam between two supports to ensure structural stability. These types of problems are excellent for promoting problem-solving and critical thinking skills.

In conclusion, teaching trigonometry can be a challenging task that requires innovative and engaging approaches. With these activities, students can learn about trigonometric ratios, how to find an angle measure, and apply these concepts to real-world scenarios. By making trigonometry relatable and tangible for students, we can help them build a strong foundation for future learning and success.