解方程2ax的平方+(4a+3)x+2a+3=0

问题描述:

解方程2ax的平方+(4a+3)x+2a+3=0

把常数项移到右边,得2ax^2+(4a+3)x=-(2a+3).
二次项系数化为1,得x^2+[(4a+3)/2a]x=-[(2a+3)/2a].
配方x^2+[(4a+3)/2a]x+(4a+3)/4a=(16a^2+24a+9)/(16a^2)-(16a^2+24a)/(16a^2)
[x+(4a+3)/4a]^2=9/(16a^2).
降次x+(4a+3)/4a=±3/4a,
即x+(4a+3)/4a=3/4a,x+(4a+3)/4a=-3/4a.
方程有两个不等的实数根x1=-1,x2=-(2a+3)/2a.

2ax的平方+(4a+3)x+2a+3=0
(2ax+2a+3)(x+1)=0
x=-(2a+3)/2a或x=-1

2ax的平方+(4a+3)x+2a+3=0
2ax²+4ax+3x+2a+3=0
2a(x²+2x+1)+3(x+1)=0
2a(x+1)²+3(x+1)=0
(x+1)(2ax+2a+3)=0
x1=-1,x2=-(2a+3)/2a