1.一元二次方程x^2-2x=255的解是______________.
问题描述:
1.一元二次方程x^2-2x=255的解是______________.
2.将2x^2+3x+1=0配方后得2(_______)^2=___________.
答
x^2-2x+1=255+1=256=16^2
(x-1)^2=16^2
x-1=16,x-1=-16
x=17,x=-15.
(2)2(x^2+3/2x)+1
=2(x+3/4)^2-1/8.