@@ -41,49 +41,29 @@ This test problem is about the optimal-time launching of a satellite into orbit
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Given by
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```math
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- \f rac{dz_1}{dt}=z_3t_f
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- ```
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- ```math
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- \f rac{dz_2}{dt}=z_4t_f
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- ```
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- ```math
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- \f rac{dz_3}{dt}=A\c os(z_5)t_f
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- ```
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- ```math
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- \f rac{dz_4}{dt}=(A\s in(z_5)-g)t_f
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- ```
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- ```math
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- \f rac{dz_5}{dt}=-z_6\c os(z_5)t_F
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- ```
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- ```math
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- \f rac{dz_6}{dt}=z_6^2\s in(z_5)t_f
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- ```
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- ```math
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- \f rac{dz_7}{dt}=0
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+ \b egin{align*}
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+ \f rac{dz_1}{dt} &= z_3 t_f, &
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+ \f rac{dz_2}{dt} &= z_4 t_f, \\
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+ \f rac{dz_3}{dt} &= A\c os(z_5) t_f, &
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+ \f rac{dz_4}{dt} &= (A\s in(z_5)-g) t_f, \\
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+ \f rac{dz_5}{dt} &= -z_6\c os(z_5) t_F, &
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+ \f rac{dz_6}{dt} &= z_6^2\s in(z_5) t_f, \\
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+ \f rac{dz_7}{dt} &= 0,
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+ \e nd{align*}
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```
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with boundary condition
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```math
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- z_1(0)=0
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- ```
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- ```math
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- z_2(0)=0
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- ```
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- ```math
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- z_3(0)=0
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- ```
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- ```math
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- z_4(0)=0
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- ```
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- ```math
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- z_5(1)=h
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- ```
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- ```math
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- z_6(1)=V_c
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- ```
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- ```math
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- z_7(1)=0
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+ \b egin{align*}
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+ z_1(0) &= 0, &
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+ z_2(0) &= 0, \\
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+ z_3(0) &= 0, &
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+ z_4(0) &= 0, \\
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+ z_5(1) &= h, &
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+ z_6(1) &= V_c, \\
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+ z_7(1) &= 0.
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+ \e nd{align*}
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```
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# Solution
@@ -134,49 +114,29 @@ Launch of a satellite into circular orbit from a flat Earth where we assume a un
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Given by
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```math
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- \f rac{dz_1}{dt}=z_3\f rac{V_c}{h}
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- ```
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- ```math
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- \f rac{dz_2}{dt}=z_4\f rac{V_c}{h}
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- ```
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- ```math
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- \f rac{dz_3}{dt}=acc\f rac{1}{|V_c|\s qrt{1+z_6^2}}
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- ```
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- ```math
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- \f rac{dz_4}{dt}=acc\f rac{1}{|V_c|\s qrt{1+z_6^2}}-\f rac{g}{V_c}
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- ```
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- ```math
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- \f rac{dz_5}{dt}=0
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- ```
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- ```math
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- \f rac{dz_6}{dt}=-z_5\f rac{V_c}{h}
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- ```
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- ```math
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- \f rac{dz_7}{dt}=0
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+ \b egin{align*}
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+ \f rac{dz_1}{dt} &= z_3 \f rac{V_c}{h}, \\ [2pt]
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+ \f rac{dz_2}{dt} &= z_4 \f rac{V_c}{h}, \\ [2pt]
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+ \f rac{dz_3}{dt} &= acc \f rac{1}{|V_c|\s qrt{1+z_6^2}}, \\ [2pt]
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+ \f rac{dz_4}{dt} &= acc \f rac{1}{|V_c|\s qrt{1+z_6^2}}-\f rac{g}{V_c}, \\ [2pt]
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+ \f rac{dz_5}{dt} &= 0, \\ [2pt]
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+ \f rac{dz_6}{dt} &= -z_5 \f rac{V_c}{h}, \\ [2pt]
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+ \f rac{dz_7}{dt} &= 0,
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+ \e nd{align*}
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```
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- with boundary condition
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+ with boundary conditions
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```math
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- z_1(0)=0
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- ```
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- ```math
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- z_2(0)=0
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- ```
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- ```math
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- z_3(0)=0
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- ```
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- ```math
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- z_4(0)=0
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- ```
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- ```math
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- z_5(1)=h
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- ```
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- ```math
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- z_6(1)=V_c
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- ```
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- ```math
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- z_7(1)=0
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+ \b egin{align*}
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+ z_1(0) &= 0, &
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+ z_2(0) &= 0, \\
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+ z_3(0) &= 0, &
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+ z_4(0) &= 0, \\
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+ z_5(1) &= h, &
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+ z_6(1) &= V_c, \\
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+ z_7(1) &= 0.
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+ \e nd{align*}
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```
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# Solution
@@ -261,49 +221,29 @@ Launch into circular orbit from a flat Earth including athmosferic drag.
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Given by
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```math
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- \f rac{dz_1}{dt}=z_3\f rac{V_c}{h}
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- ```
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- ```math
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- \f rac{dz_2}{dt}=z_4\f rac{V_c}{h}
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- ```
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- ```math
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- \f rac{dz_3}{dt}=\f rac{f}{V_c}(-\f rac{z_6}{z_6^2+z_7^2}-V_c\e ta\e xp(-z_2\b eta)z_3\s qrt{z_3^3+z_4^2})/m
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- ```
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- ```math
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- \f rac{dz_4}{dt}=\f rac{f}{V_c}(-\f rac{z_7}{z_6^2+z_7^2}-V_c\e ta\e xp(-z_2\b eta)z_4\s qrt{z_3^3+z_4^2})/m - g_{accel}/V_c
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- ```
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- ```math
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- \f rac{dz_5}{dt}=-\e ta\b eta\e xp(-z_2\b eta)(z_6z_3+z_7z_4)\s qrt{z_3^3+z_4^2}\f rac{V_c}{m}
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- ```
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- ```math
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- \f rac{dz_6}{dt}=\e ta\e xp(-z_2\b eta)(z_6(2z_3^2+z_4^2)+z_7z_3z_4)V_c/\s qrt{z_3^2+z_4^2}/m
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- ```
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- ```math
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- \f rac{dz_7}{dt}=\e ta\e xp(-z_2\b eta)(z_7(z_3^2+2z_4^2)+z_6z_3z_4)V_c/\s qrt{z_3^2+z_4^2}/m
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+ \b egin{align*}
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+ \f rac{dz_1}{dt} &= z_3 \f rac{V_c}{h} \\
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+ \f rac{dz_2}{dt} &= z_4 \f rac{V_c}{h} \\
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+ \f rac{dz_3}{dt} &= \f rac{f}{V_c} \l eft(-\f rac{z_6}{z_6^2+z_7^2} - V_c η\e xp(-z_2 β) z_3\s qrt{z_3^3+z_4^2}\r ight)/m \\
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+ \f rac{dz_4}{dt} &= \f rac{f}{V_c} \l eft(-\f rac{z_7}{z_6^2+z_7^2} - V_c η\e xp(-z_2 β) z_4\s qrt{z_3^3+z_4^2}\r ight)/m - g_{accel}/V_c \\
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+ \f rac{dz_5}{dt} &= -ηβ \e xp(-z_2 β) (z_6z_3+z_7z_4)\s qrt{z_3^3+z_4^2}\f rac{V_c}{m} \\
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+ \f rac{dz_6}{dt} &= η \e xp(-z_2 β) \l eft(z_6(2z_3^2+z_4^2)+z_7z_3z_4\r ight) V_c/\s qrt{z_3^2+z_4^2}/m \\
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+ \f rac{dz_7}{dt} &= η \e xp(-z_2 β) \l eft(z_7(z_3^2+2z_4^2)+z_6z_3z_4\r ight) V_c/\s qrt{z_3^2+z_4^2}/m \\
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+ \e nd{align*}
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```
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- with boundary condition
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+ with boundary conditions
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```math
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- z_1(0)=0
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- ```
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- ```math
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- z_2(0)=0
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- ```
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- ```math
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- z_3(0)=0
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- ```
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- ```math
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- z_4(0)=0
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- ```
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- ```math
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- z_5(1)=h
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- ```
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- ```math
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- z_6(1)=V_c
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- ```
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- ```math
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- z_7(1)=0
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+ \b egin{align*}
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+ z_1(0) &= 0, &
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+ z_2(0) &= 0, \\
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+ z_3(0) &= 0, &
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+ z_4(0) &= 0, \\
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+ z_5(1) &= h, &
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+ z_6(1) &= V_c, \\
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+ z_7(1) &= 0.
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+ \e nd{align*}
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```
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# Solution
@@ -346,22 +286,19 @@ This is an epidemiology model, about the spread of diseases.
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Given by
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```math
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- \f rac{dy_1}{dt}=\m u-\b eta(t)y_1y_3
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- ```
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- ```math
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- \f rac{dy_2}{dt}=\b eta(t)y_1y_3-y_2/\l ambda
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- ```
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- ```math
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- \f rac{dy_3}{dt}=y_2/\l ambda-y_3/\e ta
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+ \b egin{align*}
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+ \f rac{dy_1}{dt} &= μ - β(t) y_1 y_3 \\
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+ \f rac{dy_2}{dt} &= β(t) y_1 y_3 - \f rac{y_2}{λ} \\
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+ \f rac{dy_3}{dt} &= \f rac{y_2}{λ} - \f rac{y_3}{η}
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+ \e nd{align*}
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```
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with boundary condition
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```math
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- y(0)= y(1)
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+ y(0) = y(1)
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```
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-
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# Solution
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No analytical solution
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