d. 12/1312. Use the unit circle to find cos ( 7 )a.S S/-b.o. 1/2d. -1/2
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Step 1
Write the trigonometric expression
[tex]cos(\frac{7\pi}{6})[/tex]Step 2:
Step 3
[tex]cos(\frac{7\pi}{6})\text{ = -cos\lparen}\frac{\pi}{6}\text{\rparen= -cos30}\degree\text{ = -}\frac{\sqrt{3}}{2}[/tex]Final answer
[tex]-\frac{\sqrt{3}}{2}[/tex]