The unit circle shown to the right has been divided into twelve equal arcs, corresponding to t-values of 0, pi/6, pi/3, pi/2, 2pi/3, 5pi/6, pi, 7pi/6, 4pi/3, 3pi/2, 5pi/3, 11pi/6, and 2pi. Use the (x, y) coordinates in the figure to find the value of the trigonometric function at the indicated real number, t, or state that the expression is undefined.
sin 7pi/6
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