The Unit Circle | Precalculus (2026 Update) скачать в хорошем качестве

The Unit Circle | Precalculus (2026 Update)

In this lesson, 4.2 The Unit Circle, we introduce the unit circle and use it to evaluate trigonometric functions. We connect points on the unit circle to sine, cosine, and tangent, then build values using the special right triangles from the previous lesson instead of pure memorization. We practice evaluating trig functions in both degrees and radians, including quadrant angles and negative angles, and we discuss domain, range, periodic behavior, and even/odd trig identities. We also look at how coterminal angles can make evaluating trig functions easier and finish by checking values on a calculator in radian mode. 🔗 Visit www.clopensets.com for full class videos, guided notes, and printable worksheets that go along with this lesson. 🔗 ClopenSets shop: https://www.etsy.com/shop/Clopensets #education #maths #math #highschoolmath #highschool Chapters: 00:00 Introduction to the unit circle 00:16 What the unit circle is used for 00:41 Why sine is y and cosine is x 01:42 The triangle method for building unit circle values 03:03 Example: sin 60 degrees 03:59 Example: cos 240 degrees 05:05 Reference angles in radians 05:42 Example: sin 3pi over 4 06:31 Example: tan 5pi over 3 07:24 Example: cosecant 5pi over 6 08:19 Quadrant angles on the unit circle 09:23 Example: six trig functions of negative pi over 3 10:47 Domain, range, and periodic functions 11:30 Even and odd trig functions 12:09 Using coterminal angles to evaluate trig functions 14:08 Evaluating trig functions on a calculator