Question

Найдите значения выражения 5sin(a-7pi)-11cos(3pi/2+a) ,если sina= -0,25

Answer 1

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Answer 2

5sin(α-7π)-11cos(3π/2+α)=-5sin(π-α)-11cos(3π/2+α)=-5sinα-11sinα=

-16sinα=-16*(-0.25)=4