如图,已知AB是的直径,点C在上,过点C的直线与的延长线交于点P,AC=PC,。(1)求证:PC是的切线;(2)点是弧AB的中点,CM交AB于点N,求∠CNA的度数.
(乐山)计算:.
(1)计算:; (2)解不等式,并将其解集表示在数轴上.
(巴中)计算:.
(广安)计算:.
(广元)计算:.