Answer:
C. -1/2
Step-by-step explanation:
7π/6 radians is equivalent to (7π/6)(180°/π) = 210°, a 3rd-quadrant angle whose reference angle is 30°. The sine of angles in the 3rd quadrant is negative.
sin(30°) = 1/2
sin(210°) = -sin(30°) = -1/2
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In radians mode, your calculator can tell you this result directly.
C - [tex]\frac{1}{2}[/tex]
sin(7π / 6 )
note 7π\6 is in the third quadrant where sin is negative
the related acute angle to 7π/6 is 7π/6 - π = π/6
sin (7π/6) = - sin(π/6) = - [tex]\frac{1}{2}[/tex]
