No intervalo \( \biggl ] 0; \dfrac \pi 2 \biggr ] \), a equação

\( \text{x}^{3 \text{cos}(\pi / 2)} - \text{sen} \biggl ( \dfrac \pi 2 \biggr ) = \text{cos} (5\text{x}) - \text{cos} \biggl ( \text{x} + \dfrac \pi 2 \biggr ) \)

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