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this is one of my homework questions and if possible please help, I do some of it to a certain point but then get stuck. if im correct, the right choice is sin with a degree but I need some guidance. Thank you!

this is one of my homework questions and if possible please help, I do some of it-example-1
User Intensivist
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1 Answer

12 votes
12 votes

Given the expression:


2\sin 67.5\degree\cos 67.5\degree

The angle of the sine and the cosine is the same angle = 67.5°

The given expression is the same as the rule of the sine of the double angle

Where:


2\sin \theta\cos \theta=\sin (2\theta)

so, we will use the sine double-angle to solve the question

So, the answer will be:


\sin (2\cdot67.5\degree)=\sin 135\degree

So, the answer will be option B) sin 135°

User Trevin Avery
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