For the function f(x) = 1((-3(1sin(3πx + 1) + 2) + 1)/(-3(1sin(3πx + 1) + 2) + 2))^2 + 5((-3(1sin(3πx + 1) + 2) + 1)/(-3(1sin(3πx + 1) + 2) + 2)) + 4, find the number of maximal connected intervals in [-10, 10] where f'(x) < 0.

Present the answer in LaTex format: \boxed{Your answer}
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