Asked by Gabriel
                Angle x is in the first quadrant and angle y is in the second quadrant, such that Cosx = 12/13 and Siny = 7/25. Determine an exact value for Cos(x+y).
            
            
        Answers
                    Answered by
            oobleck
            
    If you draw the right triangles for x and y in standard position, you can see that
sinx = 5/13
cosy = -24/25
Now just use your sum formula
cos(x+y) = cosx cosy - sinx siny
= (12/13)(-24/25) - (5/13)(7/25) = -323/325
    
sinx = 5/13
cosy = -24/25
Now just use your sum formula
cos(x+y) = cosx cosy - sinx siny
= (12/13)(-24/25) - (5/13)(7/25) = -323/325
                                                    There are no AI answers yet. The ability to request AI answers is coming soon!
                                            
                Submit Your Answer
We prioritize human answers over AI answers.
If you are human, and you can answer this question, please submit your answer.