SOLUTION: it says 2 cos^2 30*(thirty is an angle) -1 it says Simplify to a single trig function, and then find the exact radical value to each expression below.

Algebra ->  Trigonometry-basics -> SOLUTION: it says 2 cos^2 30*(thirty is an angle) -1 it says Simplify to a single trig function, and then find the exact radical value to each expression below.       Log On


   



Question 848736: it says 2 cos^2 30*(thirty is an angle) -1
it says Simplify to a single trig function, and then find the exact radical value to each expression below.

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
2 cos^2 30*(thirty is an angle) -1
it says Simplify to a single trig function, and then find the exact radical value to each expression below.
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Note: cos(30+30) = cos30*cos30 - sin30*sin30 = cos^2(30) - sin^2(30)
= cos^2(30) - (1-cos^2(30) = 2cos^2(30) - 1
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So, 2cos^2(30)-1 = cos(60) = 1/2
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Cheers,
Stan H.
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