HOC24
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Ta có: |a-b| _<5 <=>-5_< a-b_<5
|b-c|_<8 <=>-8_<b-c_<8
|a-c|_<k <=>-k_<a-c_<k
=>-5+(-8)-(-k)_<a-b+b-c-a+c_<5+8-k
=>-13+k_<0_<13-k
<=> |0| _<13-k (1)
Mà |0|=0
13-k min
Kết hợp với 1 =>13-k=0
=>k=13
.
đặt a/c= c/b=k
=>a=ck
c=bk
=>a
1. i like watching james bond films. they r so great.
2.in my oppinion, i think play a lot of computer is not good for our eyes
3.i love beyonce knowles because she is so birilliant.
4.i don't like jim carrey because he not great.
5. i hate classical music because it is so terrible
i think anastacia is not bad