Answers:
sin(30)
1/2
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Step-by-step explanation:
The trig identity we use is
sin(A+B) = sin(A)cos(B) + cos(A)sin(B)
In this case, A = 13 and B = 17
sin(A+B) = sin(A)cos(B) + cos(A)sin(B)
sin(13+17) = sin(13)cos(17) + cos(13)sin(17)
sin(30) = sin(13)cos(17) + cos(13)sin(17)
Use a calculator or the unit circle to determine that sin(30) = 1/2