SOLUTION: Find the exact value by using a sum or difference identity. sin 75°

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Question 868199: Find the exact value by using a sum or difference identity.
sin 75°
Found 2 solutions by Edwin McCravy, htmentor:
Answer by Edwin McCravy(20059)   (Show Source): You can put this solution on YOUR website!
Using the sum identity:



sin(75°) = sin(45°+30°) = sin(45°)cos(30°) + cos(45°)sin(30°) =

    

-----------------------------------

Using the difference identity:



sin(75°) = sin(120°-45°) = sin(120°)cos(45°) - cos(120°)sin(45°) =

       

Edwin
Answer by htmentor(1343)   (Show Source): You can put this solution on YOUR website!
Since 75 = 45 + 30, we can use the following identity:

This can be simplified to
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