document.write( "Question 1137787: Prove that cos35 + cos45 + cos75 + cos85 = 2cos5cos20 \n" ); document.write( "
Algebra.Com's Answer #755698 by Alan3354(69443)\"\" \"About 
You can put this solution on YOUR website!
Using a calculator, they are equal.
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\n" ); document.write( "I don't plan to do any more on this one.
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