Math CentralQuandaries & Queries


Question from Jason, a student:

Please Help! My question is :

Find all of the solutions to sin(x/2)+cosx-1=0


I can help get you started. Let y = x/2 and then the equation becomes

sin(y) + cos(2y) - 1 = 0.

Use the double angle expression for the cosine and if necessary use the fact that sin2(y) + cos2(y) = 1 to express the equation without the cosine function.

Write back if you need more assistance,


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