小学生的大问题

manthanein

\(\D \frac{170-63k}{20}\)
\(\D \frac{200-63k}{20}\)

manthanein

\(\D F(x)=mx+n\left\lceil{\D \frac{u-ax}{b}} \right\rceil\)
\(\D F(0)=n \left\lceil{\frac{u}{b}} \right\rceil\)

所以线段所在直线方程为\(\D y=m(x+k\frac{b}{a})+n \left\lceil{\frac{u}{b}} \right\rceil\)

manthanein

\(\D y=mx+{\frac{n(u-ax)}{b}}\)
\(\D y=m(x+k\frac{b}{a})+n \left\lceil{\frac{u}{b}} \right\rceil\)
\(\D \frac{n(u-ax)}{b}=\frac{mkb}{a}+n \left\lceil{\frac{u}{b}} \right\rceil\)
\(\D an(u-ax)=mkb^2+abn \left\lceil{\frac{u}{b}} \right\rceil\)