For the function f(x) = -5(2|(2cos(1π((3x - 2)/(-3x + 4)))) + 1| - 3)^2 + 5(2|(2cos(1π((3x - 2)/(-3x + 4)))) + 1| - 3), 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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