x^2+2x+3=0 x^2+2x+4=0 2x^2-3x-5=0 4x^2-8x-3=0 4x(x-3)-3(x-3)=-5 过程谢谢~一元二方程~急~~~~~~~

2024-12-23 05:28:22
推荐回答(1个)
回答1:

x²+2x+3=0
△<0
无解

x²+2x+4=0
△<0
无解

2x²-3x-5=0
(x+1)(2x-5)=0
解得x=-1或x=5/2

4x²-8x-3=0
x=[-b±√(b²-4ac)]/2a
解得x=-1±½√7

4x(x-3)-3(x-3)=-5
4x²-15x+2=0
x=[-b±√(b²-4ac)]/2a
解得x=(15±√193)/8

望采纳,O(∩_∩)O谢谢