SOLUTION: How do you solve cos(45degrees + 30degrees) using trigonomic identities?

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Question 254156: How do you solve cos(45degrees + 30degrees) using trigonomic identities?
Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
The question was:
(i) cos%2845+%2B+30%29
We have the following identity:
cos%28A%2BB%29+=+cosAcosB+-+sinA+sinB
So, (i) becomes
(ii) cos%2845+%2B+30%29+=+cos45cos30+-+sin45+sin30
or

which is
cos%2845+%2B+30%29+=+%28sqrt%286%29+-+sqrt%282%29%29%2F4