I need to find the value of the trigonometric function y=(1/2)sin(2x-2π), x's range is (π/3 ; 5π/8), i am okay with the first few steps :

π/3 < x < 5π/8 |*2

2π/3 < 2x < 5π/4 | - 2π

-4π/3 < 2x - 2π < - 3π/4

However, here's when i get confused

How should i solve the rest of the problem?

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