Question

Answer 1

a: |x-35|+|x+15|

=|x+15|+|35-x|>=|x+15+35-x|

=50

b: |2x-7|+|8+2x|

=|2x+8|+|7-2x|>=|2x+8+7-2x|=15

c: Đặt \(A=\left|x+3\right|+\left|2x-13\right|+\left|x+4\right|\)

=>\(A\ge\left|x+3-2x+13\right|+\left|x+4\right|\)

=>A>=|-x+16|+|x+4|

=>A>=|-x+16+x+4|

=>A>=|20|

=>A>=20