来自郭恒昌的问题
①:(x+5)^2=3(x+5)②:(x-4)^2-x+4=0③:3(x+1)(x-2)=2(X^2-1)
①:(x+5)^2=3(x+5)②:(x-4)^2-x+4=0③:3(x+1)(x-2)=2(X^2-1)
3回答
2020-01-14 16:32
①:(x+5)^2=3(x+5)②:(x-4)^2-x+4=0③:3(x+1)(x-2)=2(X^2-1)
①:(x+5)^2=3(x+5)②:(x-4)^2-x+4=0③:3(x+1)(x-2)=2(X^2-1)
1、x+5=0或不为0
是0时x=-5;不为0,两边消去x+5,得x=-2
2,同理1,x=4或者x=5
3,同理x^2-1=(x-1)(x+1)
当x+1=0时或不为0
得x=-1或x=4
4(x-3)^2+x(3-x)=0(3x-1)^2=4(2x-3)^2这两题怎么做啊?
4(x-3)^2+x(3-x)=0这个跟前几个一样啊,移项4(x-3)^2=x(x-3)得到x=3或x=4这个(3x-1)^2=4(2x-3)^2就需要展开了9x^2-6x+1=16x^2-48x+367x^2-42x+35=0x^2-6x+5=0x=1x=5