How do you find the exact value of #sin(pi/3)cos(pi/7) - cos(pi/3)sin(pi/7)#?
1 Answer
Jun 24, 2016
Explanation:
Notice that this fits the form of the sine subtraction formula:
#sin(A-B)=sin(A)cos(B)-cos(A)sin(B)#
Here, we see that
#sin(pi/3-pi/7)=sin(pi/3)cos(pi/7)-cos(pi/3)sin(pi/7)#
So, the entire expression equals:
#sin(pi/3-pi/7)=sin((4pi)/21)#
This is a more exact form of what was given, although it is still equivalent.