[考古] 99政大金融系

[weiming (瑋)]

A company's sales rate is x^2 exp{-x} million sales
per month after x months.
Find a formula for the total sales in the first x months.

請問有人知道這要怎麼算嗎？謝謝大家

--
※ 發信站: 批踢踢實業坊(ptt.cc) 
◆ From: 115.43.220.127