Question

Rút gọn :

M = \(\left|x-5\right|\) - 3.(2-x)-3

N = -8.(1-x)+\(\left|x+6\right|-\left|x+1\right|\)

Answer 1

a: \(M=\left|x-5\right|-6+3x-3=\left|x-5\right|+3x-9\)

Trường hợp 1: x>=5

M=x-5+3x-9=4x-14

Trường hợp 2: x<5

M=5-x+3x-9=2x-4

b: \(N=-8+8x+\left|x+6\right|-\left|x+1\right|\)

\(=\left|x+6\right|-\left|x+1\right|+8x-8\)

Trường hợp 1: x<-6

N=-x-6-(-x-1)+8x-8

\(=7x-14+x+1=8x-13\)

Trường hợp 2: -6<=x<-1

\(N=x+6-\left(-x-1\right)+8x-8\)

\(=9x-2+x+1=10x-1\)

Trường hợp 3: x>=-1

\(N=x+6-x-1+8x-8=8x-3\)