Answer:
4 and -18
Step-by-step explanation:
Answer:

Step-by-step explanation:

Collect like terms
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Calculate
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Hope I helped!
Best regards! :D
Answer:
D. -√3/2
Step-by-step explanation:
Remember your unit circle.
Alternatively, you can plug in cos(7π/6) into your calc (Put it in rad mode) and calculate your answer.