How do you solve #cos 2x = - sqrt3 / 2# using the double angle identity?
1 Answer
Oct 13, 2015
Solve:
Ans:
Explanation:
Solving by double angle identity:
cos x = +- sqrt(2 - sqrt3)/2 = +-0.517/2 = +- 0.258
a. cos x = 0.258 -->
b. cos x = - 0.258 -->
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