Question

calcule:
-2/3 x cos3pi/2 + 3/5 x cos5pi/3 - 6/7 x cos7pi/6
obs. esse x é de multiplicação.

Answer 1

Resposta:

-2/3.cos3π/2 + 3/5.cos5π/3 - 6/7.cos7π/6=3/10+3√3/7

Explicação passo-a-passo:

cos3π/2=cos(3.180°/2)=cos(270°)=0

cos5π/3=cos(5.180°/3)=cos(300°)= cos(60°)= 1/2

cos7π/6=cos(7.180°/6)=cos(210°)= -cos(30°)= -√3/2

-2/3.cos3π/2 + 3/5.cos5π/3 - 6/7.cos7π/6=

-2/3.0 + 3/5.1/2 - 6/7.(-√3/2)=

3/10+3√3/7