y=-2x²+4x+1=x²-2x-1/2=x²-2x+1-1-1/2=(x-1)²-3/_数学解答

y=-2x²+4x+1
=x²-2x-1/2=x²-2x+1-1-1/2=(x-1)²-3/2【错在哪啊?正确步骤是什么?】

人气：285 ℃　时间：2020-04-13 02:04:48

解答

y=-2x²+4x+1
=-2(x²-2x-1/2)
=-2(x²-2x+1-1-1/2)
=-2[(x-1)²-3/2]
=-2(x-1)²+3
你前面的系数-2呢