设P(x,y),M(x',y')
依题意,向量OM=2向量MP
则(x',y')=2(x-x',y-y')
即x'=2(x-x'),y'=2(y-y')
则x'=2/3x,y'=2/3y
因y'=1/2x'²
故2/3y=1/2(2/3x)²
整理得x²=3y
它是顶点在原点,焦点为(0,3/4)的抛物线.
设P(x,y),M(x',y')
依题意,向量OM=2向量MP
则(x',y')=2(x-x',y-y')
即x'=2(x-x'),y'=2(y-y')
则x'=2/3x,y'=2/3y
因y'=1/2x'²
故2/3y=1/2(2/3x)²
整理得x²=3y
它是顶点在原点,焦点为(0,3/4)的抛物线.