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

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Answer 1 · 2016-04-11T04:16:34

$(sin((11pi)/24)-sin((5pi)/24))/2$

Use
$sin 2A - sin 2B = 2 cos(A+B)sin(A-B)$ .

Here, $A+B=pi/3 and A-B=pi/8$ .

So, $2A=11pi/24 and 2B=5pi/24$ .

Answer: $(sin((11pi)/24)-sin((5pi)/24))/2$

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