Fri July 20, 2012 By:

In the video where you explained the formula of sin(x+y)the angle CBA is not equal to x. It is commoning y can you explain the angle of CBA

Expert Reply
Tue July 24, 2012
Since BE is perpendicular to OD, so angle BEO is 90 degrees.
So, in triangle POE, angle OPE = 90 - x (using angle sum property)
So, angle CPA is also 90 - x (vertically opposite angles)
In right triangle APB, by angle sum property, we get,
angle ABP = x
That is, angle CBA = x
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