Asking for a value of trigonometri

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The value of sin(180 - theta/2) can be derived using trigonometric identities, specifically sin(A - B) = sin A cos B - cos A sin B. Since sin(180) equals 0 and cos(180) equals -1, the expression simplifies significantly. To express sin(180 - theta/2) in terms of theta, one can also utilize the identity for sin(theta/2), which is ±√((1/2)(1 - cos(theta))). The discussion emphasizes the importance of clarifying the desired output, whether it be a numerical value or a function of theta. Overall, the conversation highlights key trigonometric principles necessary for solving the problem.
Sanosuke Sagara
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I want to ask for what is the value for sin (180-theta/2) ?Thanks for anybody that spend time looking on my problem.
 
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Use the fact that sin (A - B) = sin Acos B - cos Asin B.
 
Well, first use the fact that sin(A+B)= sin(A)cos(B)+ cos(A)sin(B)!

And, of course, sin(180)= 0 while cos(180)= -1 (I assume this is in degrees- you didn't actually say so).

If you want this as a function of theta only (again, you didn't say what you really wanted), you will also need to know that sin(theta/2)= +/- √((1/2)(1- cos(theta)).
 
Yeah, sorry that's what I meant :smile:. I thought it was obvious to then plug in the values of sin 180 and cos 180.
 

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