Trigonometry Identities: sin(x +/- y) = sin(x)cos(y) +/- cos(x)sin(y)

in MES Science21 days ago (edited)

In this video I use the cos(x - y) identity which I proved in my earlier video to derive a very useful trigonometric identity for sin(x + y) and sin(x -y).

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Trigonometry Identities

Trig Identities - Sub add sin(x+y) Resized AI.jpg

Addition and Subtraction Formulas

Addition: sin(x + y) = sin(x)cos(y) + cos(x)sin(y)


Subtraction: sin(x - y) = sin(x)cos(y) - cos(x)sin(y)



Sine and Cosine Addition / Subtraction Identities


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