论文部分内容阅读
问题1:已知异面直线a、b所成角为60°,过空间一点P作直线与直线a、b都成45°的直线共有_____条。问题2:已知直线l与平面α所成的角为70°,过空间一点P与直线l和平面α都成45°角的直线共有____条。问题3:已知平面α与平面β所成的角为80°,点P为α、β外一定点,过点P的直线与α、β所成的角都是30°,则这样的直线有_____条。
Question 1: It is known that the angles formed by the non-planar straight lines a and b are 60°, and the line that passes the point P and the straight lines a and b both form 45° have _____. Question 2: It is known that the angle formed by the straight line l and the plane α is 70°, and the line passing through the space P and the straight line l and the plane α both having a 45° angle is ____. Question 3: It is known that the angle formed by the plane α and the plane β is 80°, the point P is a certain point outside the α, β, the angle formed by the straight line crossing the point P and α, β is 30°, and such a straight line There are _____ articles.