SOLUTION: Evaluate cos45°cos30°-sin45°sin30°

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Question 982816: Evaluate cos45°cos30°-sin45°sin30°
Found 2 solutions by Cromlix, Alan3354:
Answer by Cromlix(4381) About Me  (Show Source):
You can put this solution on YOUR website!
Hi there,
cos45°cos30°-sin45°sin30°
1/root2 * root3/2 - 1/root2 * 1/2
= (root3 - 1)/2 root2
Hope this helps:-)

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Evaluate cos45°cos30°-sin45°sin30°
===========
= cos(45+30)
= cos(75)
--------------
= sqrt%282+-+sqrt%283%29%29%2F2
Also,
= %28sqrt%286%29+-+sqrt%282%29%29%2F4