Question

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!

Answer 1

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°