计算.
下列说法中错误的是( )
关于x的不等式ax2+bx+c>0的解集为(﹣1,3),则关于x的不等式ax2﹣bx+c>0的解集为____.
—— __________ do you chat by QQ with your friend in Shanghai every week?——Two hours. I have much homework to do every day.