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Question
Find the value of the following:
`sin pi/4 cos pi/12 + cos pi/4 sin pi/12`
Solution
This is of the form sin(A + B) = sin `(pi/4 + pi/12)`
`= sin ((3pi + pi)/12)`
`= sin (4pi)/12`
`= sin (pi)/3`
`= sqrt3/2 ...(because sin 60^circ = sqrt3/2)`
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