Question 859783
{{{sin(x+y)=sin(x)cos(y)+cos(x)sin(y)}}}
{{{sin(x-y)=sin(x)cos(y)-cos(x)sin(y)}}}
So,
{{{sin(x+y)-sin(x-y)=sin(x)cos(y)+cos(x)sin(y)-sin(x)cos(y)+cos(x)sin(y)}}}
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{{{sin(x+y)-sin(x-y)=2cos(x)sin(y)}}}