How do you express #sin(pi/12) * cos((3pi)/8 ) # without products of trigonometric functions?

Question

1451 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-03-24T00:09:14

#\sin(\pi/12)\cos(3\pi/8)#

#=(1/2)(\sin(11\pi/24)-\sin(7\pi/24))#

Use these identities to simplify this kind of product:

#\sin(a)\sin(b)#

#=(1/2)(\cos(a-b)\cos(a+b))#

#\sin(a)\cos(b)#

#=(1/2)(\sin(a+b)+\sin(a-b))#

#=(1/2)(\sin(a+b)-\sin(b-a))#

#\cos(a)\cos(b)#

#=(1/2)(\cos(a+b)+\cos(a-b)#