Which of the following expressions could not be used to determine the exact value of cos 120°? O cos^2(60°) - sin^2(60°)

Question

Which of the following expressions could not be used to determine the exact value of cos 120°?
O cos^2(60°) - sin^2(60°)
O2cos^(60°) - 1
O 2sin(60°)cos(60°)
O 1 - 2sin^2(60°)

Kunduz · Accepted Answer

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