Quizzes over applying Unit Circle concepts were returned today. Make sure you understand your mistakes.
Don't forget that you are always supposed to be making connections between degrees, radians and coordinates on the unit circle. It can help with many homework problems.
Today our big ideas were two-fold and very different:
Can you use trig ratios to solve for unknowns in right triangles (just like you did in Geometry)? We practiced some in class from the old geometry textbooks in my room.
What is a trig identity?
As a starter: trig identities are just our definitions of the six trig functions in terms of each other. Like sin = 1/csc. etc. You will also be asked to define all 6 of them in terms of a labeled triangle like our warm-up today. We learned about the identities based on the Pythagorean Theorem in a right triangle with hypotenuse of 1 in quadrant I. We also learned about the cofunction identities, using our warm-up to lead to the idea that the sine of an acute angle is the cosine of its complement.
Most of the identities are on p 280 in the textbook. I am also adding a photo of our notes with the identities that are not on p 280.
You will have a quiz next block over the basics of the trig identities. Please use the flash card link in the post right below this one to make sure that you know them.
HW #6 was more from the same section with a focus on the application problems that are a bit like the geometry book: pp 285-6: 63-67, 74-75, 77-78, 82. AND LEARN YOUR TRIG IDENTITIES: warm-up, + p 280 box, + cofunction identities + even/odd identities (bottom of notes page).
NEXT CLASS IS VERY IMPORTANT. WE WILL BE LEARNING TO DO TRIG IDENTITY PROOFS IN CLASS.
Don't forget that you are always supposed to be making connections between degrees, radians and coordinates on the unit circle. It can help with many homework problems.
Today our big ideas were two-fold and very different:
Can you use trig ratios to solve for unknowns in right triangles (just like you did in Geometry)? We practiced some in class from the old geometry textbooks in my room.
What is a trig identity?
As a starter: trig identities are just our definitions of the six trig functions in terms of each other. Like sin = 1/csc. etc. You will also be asked to define all 6 of them in terms of a labeled triangle like our warm-up today. We learned about the identities based on the Pythagorean Theorem in a right triangle with hypotenuse of 1 in quadrant I. We also learned about the cofunction identities, using our warm-up to lead to the idea that the sine of an acute angle is the cosine of its complement.
Most of the identities are on p 280 in the textbook. I am also adding a photo of our notes with the identities that are not on p 280.
You will have a quiz next block over the basics of the trig identities. Please use the flash card link in the post right below this one to make sure that you know them.
HW #6 was more from the same section with a focus on the application problems that are a bit like the geometry book: pp 285-6: 63-67, 74-75, 77-78, 82. AND LEARN YOUR TRIG IDENTITIES: warm-up, + p 280 box, + cofunction identities + even/odd identities (bottom of notes page).
NEXT CLASS IS VERY IMPORTANT. WE WILL BE LEARNING TO DO TRIG IDENTITY PROOFS IN CLASS.
identity_notes_9-4.pdf |