SOLUTION: Given: cos (-105)
Find the exact value of the function without the use of a calculator.
I was unsure what to do with a negative, but from examples, I did the following where it
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-> SOLUTION: Given: cos (-105)
Find the exact value of the function without the use of a calculator.
I was unsure what to do with a negative, but from examples, I did the following where it
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Question 1114896: Given: cos (-105)
Find the exact value of the function without the use of a calculator.
I was unsure what to do with a negative, but from examples, I did the following where it "ignores" the negative.
cos (105) = cos (135 - 30)
Final Answer:
If the final answer is right, why does the (-) go away and if that procedure is incorrect how would you split up the -105? Thank you for any help! Answer by ikleyn(52798) (Show Source):
cos(a) = cos(-a) for any angle "a".
In particular, cos(-105°) = cos(105°), so your result is applicable to cos(-105°).
Your final result is RIGHT: cos(-105°) = .
