拋物線y=x²-3x+2與直線y=-x+3的交點(diǎn)有 個
x²-3x+2=-x+3
x²-2x+1=2
(x-1)²=2
x-1=±√2
當(dāng)x=1+√2或1-√2時,拋物線與直線相交
交點(diǎn)有兩個