Question 682513
Use a sum or difference formula to find the exact value of the trigonometric function
cos 75degree
simplyfy the answer including any radicals
use integers or fractions for any number in the expression
rationalize all denominators
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Identity: (s+t)=cos s cos t-sin s sin t
cos(75)=cos(45+30)=cos 45 cos 30-sin 45 sin 30
=√2/2*√3/2-√2/2*1/2
=√6/4-√2/4
=(√6-√2)/4