Reflection: Pacing Sum and Difference Day 1 of 2 - Section 1: Bell Work


I routinely discuss how a calculator give approximate values for irrational numbers. This is good in some cases but in this situation if you are dealing with angles in space or on the earth where you round can make a big difference to position. Scientist will wait until the final calculation to round so they do not accumulate error that can cause major problems.

To make the point I will compare the distance between the terminal side of a 74 degree anlge to a 75 degree angle. If necessary I will get out my smart protractor and draw the angles. You could also use Geogebra for this demonstration.



  Calculator approximations
  Pacing: Calculator approximations
Loading resource...

Sum and Difference Day 1 of 2

Unit 9: Trigonometric Identities
Lesson 9 of 14

Objective: SWBAT prove the sum and difference formulas for sine, cosine and tangent

Big Idea: After analyzing a proof for the sum of angles sine formula, students work to produce the other sum and difference formulas.

  Print Lesson
2 teachers like this lesson
Math, Trigonometric identities, sum and difference formulas
  70 minutes
team work
Similar Lessons
Does cos(A - B) = cos(A) - cos(B)?
12th Grade Math » Trigonometric Relationships
Big Idea: Students disprove a potential identity and then derive the real cos(A - B) formula.
Troy, MI
Environment: Suburban
Tim  Marley
Playing with the Numbers
Algebra II » Trigonometric Functions
Big Idea: Students transform equations and graphs of trig functions to earn points and win the game!
Craigmont, ID
Environment: Rural
Merrie Rampy
Something went wrong. See details for more info
Nothing to upload