Question

Tính nhanh

6,5+1,2+3,5-5,2+6,5-4,8

(-4,3.1,1+1,1.4,5).(-0,5.0,05+10,01)

(6,7+5,66-3,7+4,34).(-76,6.1,2+7,66.12)

Tìm x

|12,1.x+12,1.0,1|=12,1

|0,2.x-3,1|+|0,2+3,1|=0

Answer 1

bài 2)

a)|12,1x+12,1.0,1|=12,1

<=> |12,1(x+0,1)|=12,1

<=>\(\left[\begin{array}{nghiempt}12,1\left(x+0,1\right)=12,1\\12,1\left(x+0,1\right)=-12,1\end{array}\right.\)

<=> \(\left[\begin{array}{nghiempt}x=0,9\\x=-1,1\end{array}\right.\)

b) |0,2x-3,1|+|0,2+3,1|=0

<=>|0,2x-3,1|+3,3=0

ta có |A|>=0

=> pt trên vô nghiệm

bài 1) a) 6,5+1,2+3,5-5,2+6,5-4,8

=(6,5+3,5+6,5)-(5,2-1,2+4,8)

=15,5-8,8=24,6

tt nha bạn