Helen was so excited at the news that she could say a word.
求经过直线l1:3x+2y﹣1=0和l2:5x+2y+1=0的交点,且垂直于直线l3:3x﹣5y+6=0的直线l的方程.
对下列实验中出现的异常现象分析合理的是( )
若抛物线x2=2py的焦点为F(0,2),则p的值为( )