(1)
â£2aâ£=â£3a+6â£
â 2a>0, 3a+6>0,
2a=3a+6, a=-6, ä¸åè¦æ±ï¼èå»
â¡2a
0,
-2a=3a+6, a=-6/5, ✔
â¢2a>0, 3a+6<0,
2a=-(3a+6ï¼, a=-6/5, ä¸åè¦æ±ï¼èå»
â£2a<0, 3a+6<0,
-2a=-(3a+6), a=-6, ✔
ï¼2ï¼
( 0+(3-(-2)), 2+(-1-3))â(5,-2)
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ä»ä¹ææ
追ç横åæ æ¯0+[3-(-2)]=5,
纵åæ æ¯2+(-1-3)=-2