Which of the following are equivalent to the function y=3cos x + 2? Check all that apply. (attached below)

Please explain. Thank you!

Question

Which of the following are equivalent to the function y=3cos x + 2? Check all that apply. (attached below)

Please explain. Thank you!

kj4uts · Answer

attachment

danjs · Answer

did you learn symmetries of the unit circle

danjs · Answer

For example,  The cosine function is the X value of a point on the unit circle

If you put in the angle Theta, and the angle -theta, you get the same cosine

danjs · Answer

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kj4uts · Answer

That would make it B. and C. then?

danjs · Answer

Yes, Answer B is seen above, andlooking a little closer answer C is also in the diagram

Sin(theta) = sin(theta +90) pr sin(theta + pi/2)

danjs · Answer

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