→ novin:平均不等式 !? 推 61.217.58.205 02/14
→ alan1003:平均不是用來算最小值? 推 140.112.25.200 02/14
→ novin:想錯了... >< 推 61.217.58.205 02/14
→ novin:作圖...... (別打我) 推 61.217.58.205 02/14