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I asked a question but got no answer.? Need help to understand why this equation is different from the formulas given. Write each product as a sum or difference
1. cos(10x)sin(5x)? 5√2 -4√18 + √36 = 6-7√2. Can someone explain how this problem is done and why that's the answer? Quadrilateral ABCD with vertices? Where are you going to watch the eclipse on the west coast of the US?