Question

数学题求解速度

速度啊，

Answer 1

1先求出a 和b来根据 a2 =b2+c2得方程组为{√6c= b2+c2 b2+c2=4
解得c=4√6 /6 a2=4, b2=4/3故可以画出椭圆图来
2 为长轴的坐标是（0,1）所以长轴落在y轴上 先列出三个坐标来 分别为（0,1） （b ,0） (c,0) 因为其坐标组成的是一个正方形所以b2+1= (b-c)2 且1= b2+c2
根据方程组得b2=3/4 c2=1/4 a2=1
3 将（0，2）带入椭圆方程得b2=4 MF1+MF2=2a=8得a=4 故c2=16-4=12

Answer 2

The United States once had the highest graduation rate of any nation. Now it stands 10th. For the first time in American history, there is the risk that the rising generation will be less well educated than the previous one. The graduation rate among 25- to 34-year-olds is no better than the rate for the 55- to 64-year-olds who were going to college more than 30 years ago. Studies show that more and more poor and non-white students want to graduate from college – but their graduation rates fall far short of their dreams. The graduation rates for blacks, Latinos, and Native Americans lag far behind the graduation rates for whites and Asians. As the minority population grows in the United States, low college graduation rates become a threat to national prosperity.

Answer 3

MN+MP=3＋1＝4

Answer 4

MN+MP=4

Answer 5

MN/+/MP/=3+1=4

Answer 6

字迹不清，无法辩解