Сравни числа

1. \(\sin \left(-\dfrac{\pi }{2}\right)\) [ \(\gt\) | \(\lt\) | \(=\) ] \(-\cos \dfrac{2\pi }{3}\) ;

2. \(\sin \left(-\dfrac{5\pi }{4}\right)\) [ \(\gt\) | \(\lt\) | \(=\) ] \(\cos \dfrac{5\pi }{4}\) .