抛物线y=x²-2x-c的顶点在y=2x-1上,求c的值

问题描述:

抛物线y=x²-2x-c的顶点在y=2x-1上,求c的值

y=x²-2x-c= (x-1)²-(c+1),顶点(1,-(c+1))在y=2x-1上
-(c+1) = 2*1-1 = 1
c=-2