Question

10cos2α, если sinα=0,5.

Answer 1

sin²a+cos²a=1

cos²a=1 - sin²a

cos²a =1 - (0.5)²

cos²a = 0.75

cos2a =cos²a -sin²a

cos2a = 0.75 - (0.5)²

cos2a = 0.5

10cos2a= 10* 0.5

10cos2a =5

Ответ 5