Cos²30°-sin²30°= 2sin15°cos15°=

Question

Cos²30°-sin²30°=
2sin15°cos15°=

Answer 1

9Cos²30°-sin²30°=(√2/2)в квадрате - 0.5 в квадрате =1/2-0,25=0,25
2sin15°cos15°=sin(2*15)=0.5

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