①sin(-π/4)②sin13/6π③cos5/4π④tan(-7/4π)⑤-cos(-300°)⑥sin495°

问题描述:

①sin(-π/4)②sin13/6π③cos5/4π④tan(-7/4π)⑤-cos(-300°)⑥sin495°

①-√2/2②1/2③同① ④1⑤√3/3⑥同①