Reflection: Connection to Prior Knowledge Solving Trig Equations - Section 1: Launch and Explore

Sometimes the little things are the most rewarding. While trying to solve 4(sinx)^2 + 8sinx = -3, I saw this student rewrite the equation as 4x^2 + 8x +3 = 0. I was so excited that the student realized that the structure of this equation was basically the same as a simple quadratic! In addition, I was even more excited that this strategy was something we already discussed when we solved log equations. I hope that our earlier work stuck with her and she made that connection. Regardless, it was awesome that she understood that this equation looks a lot more difficult than it actually is and that she can use familiar tools to solve an unfamiliar equation.

Connection to Prior Knowledge: The Little Things

Solving Trig Equations

Unit 5: Trigonometric Relationships
Lesson 9 of 15

Big Idea: Why do these trig equations have so many solutions?

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Standards:
55 minutes

Tim Marley

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