100 Points! Algebra question. Photo attached. Find the exact value of the expression. Please show as much work as possible. Thank you!
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Answer:
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The cosine function has a period of 360°, we can subtract 360° from 375° to find the co-terminal angle:
Now, we can find the exact value of cos(15°) using the angle addition formula for cosine:
The exact value of cos(375°) is (√6 + √2) / 4.