Assessment for Identities

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SWBAT use identities to verify other identities and evaluate trigonometric functions

Big Idea

Through a written assessment students demonstrate their proficiency in using trigonometric identities to verify identities and evaluate trigonometric functions.


45 minutes

For this assessment students are allowed to use the reference sheet they developed during the unit. The one shared was typed by a students and shared with anyone that wished to have the sheet.

I allow the use of the identity sheet because the main goal of this unit is for students to use the identities.  I also teach calculus and I find that the students know the important identities even though I do not have them memorize them for this test.

On this test, I do allow students to get a hint on the first 2 questions if they get stuck.  I will deduct points by determining how much of a hint the student needed.  Correcting a sign error is not as much of an error as reminding students of the property needed to start the problem.

Question 3 on the test allows students to show their reasoning.  I did not state which formula to use so the students can solve it many different ways.

Students sometimes struggle with question 4.  I made cos B=-3/4 to make sure students realize that just because you see a 3 and a 4 the other side (y in this case) is not necessarily 5.  That is a common error.  The other error is simplifying with radicals. Some students are not sure how to write (3)(-sqrt21). We have briefly reviewed this in class but many panic on tests and forget what happened on homework.

On the last 2 problems students struggle with computations with fractions. This is an issue I work on throughout the course.  I try to work with students on an individual basis to fix the errors or misconceptions.