因式分解法解方程X2+3aX+2a2-a-1=0字母后面的数为2次方,

问题描述:

因式分解法解方程
X2+3aX+2a2-a-1=0字母后面的数为2次方,

X²+3aX+2a²-a-1
=x²+3ax+(2a+1)(a-1)
=(x+2a+1)(x+a-1)=0
x+2a+1=0或x+a-1=0
x1=-2a-1
x2=1-a