椭圆x^2/4+y^2/3=1与抛物线y^2=4x有两个关于横轴对称的点, 但如果将此两个方程联立消y, 可得3x^2+16x-12=0,其判别式不为0,且有两个异号根, 如何与学生解释这个现象??因为学生认为两曲线交点横坐标相等,消元后的关于x方程的判别式应该为0?

The f utureoftheWorldWildlifeFund's symbolisfarfromcertain.

a brightest boy这样说明“一个非常聪明的男孩”可以吗

National borders allow inequalities.

1.In the factory there is a transformer____is painted the word "danger".A. whichB. on whichC.whereD.on where2.When someone says that he has a good memory, he actually means that he_____ his memory by practising exercising it.A. wantsB. builds upC. makesD. keeps ...