M(-2,0),N(2,0),P(x,y)MN=(4,0)MP=(x+2,y)NP=(x-2,y)|MN|=√(4^2+0^2)=4|MP|=√[(x+2)^2+y^2]MN*NP=4(x-2)+0*y=4x-8|MN||MP|+MN*NP=04√[(x+2)^2+y^2]+4x-8=0√[(x+2)^2+y^2]=2-x(x+2)^2+y^2=(2-x)^2[(x+2)+(2-x)][(...
高中数学这个题有没有会的
M(-2,0),N(2,0),P(x,y)MN=(4,0)MP=(x+2,y)NP=(x-2,y)|MN|=√(4^2+0^2)=4|MP|=√[(x+2)^2+y^2]MN*NP=4(x-2)+0*y=4x-8|MN||MP|+MN*NP=04√[(x+2)^2+y^2]+4x-8=0√[(x+2)^2+y^2]=2-x(x+2)^2+y^2=(2-x)^2[(x+2)+(2-x)][(...