1.由已知得,半焦距c=√3,短半轴长b=√3/2,则长半轴长a=√15/2,则椭圆C的标准方程为:x^2/(15/4)+y^2/(3/4)=12.设直线L方程为:y=kx+1/2,与椭圆交点坐标为M(x1,y1)N(x2,y2),P(x,y),则x=1/2*(x1+x2),y=1/2*(y1+y2)直线y=kx+1/2代入椭圆x^2/(15/4)+y^2/(3/4)=1得:x^2/(15/4)+( kx+1/2)^2/(3/4)=1,(5*k^2+1)x^2+5*k*x-5/2=0,则x1+x2=-5*k/(5*k^2+1)直线y=kx+1/2变为x=(y-1/2)/k,代入椭圆x^2/(15/4)+y^2/(3/4)=1得:...
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