SOLUTION: Will you please help me with this equation: Given: sin (x+y)=sin x cos y + cos x sin y and cos (x+y) = cos x cos y - sin x sin y. Simplify ; sin ( x + pi ) × tan (x +pi/2) × sec

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Question 1010663: Will you please help me with this equation: Given: sin (x+y)=sin x cos y + cos x sin y and cos (x+y) = cos x cos y - sin x sin y. Simplify ; sin ( x + pi ) × tan (x +pi/2) × sec (pi/2 - x)
Answer by jim_thompson5910(35256)   (Show Source): You can put this solution on YOUR website!
Let's break the problem into smaller pieces


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Use the given identity


Use the unit circle


Multiply


Simplify. We'll call this Equation A


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Use the given identity


Use the unit circle


Multiply


Simplify. We'll call this Equation B


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Use the given identity


Use the unit circle


Multiply


Simplify. We'll call this Equation C


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Use the given identity


Use the unit circle


Multiply


Simplify. We'll call this Equation D


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Use the identity sec = 1/cos.


Substitute (see Equation D). We'll call this Equation E


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Use the identity tan = sin/cos


Perform a substitution (see equation B)


Perform a substitution (see equation C)


Simplify. We'll call this Equation F


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Now onto the main problem


Original Given Problem


Apply a substitution (see equation A)


Apply a substitution (see equation F)


Apply a substitution (see equation E)




















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So, simplifies to

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