{VERSION 3 0 "APPLE_PPC_MAC" "3.0" } {USTYLETAB {CSTYLE "Maple Input" -1 0 "Courier" 0 1 255 0 0 1 0 1 0 0 1 0 0 0 0 }{CSTYLE "2D Math" -1 2 "Times" 0 1 0 0 0 0 0 0 2 0 0 0 0 0 0 }{CSTYLE "2D Output" 2 20 "" 0 1 0 0 255 1 0 0 0 0 0 0 0 0 0 } {PSTYLE "Normal" -1 0 1 {CSTYLE "" -1 -1 "" 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 }0 0 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }{PSTYLE "Maple Output" 0 11 1 {CSTYLE "" -1 -1 "" 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 }3 3 0 -1 -1 -1 0 0 0 0 0 0 -1 0 }} {SECT 0 {EXCHG {PARA 0 "" 0 "" {TEXT -1 12 "Brian Lefler" }}{PARA 0 " " 0 "" {TEXT -1 13 "Sherri Sisler" }}{PARA 0 "" 0 "" {TEXT -1 9 "Amy O zmon" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 37 "M aple Worksheet pg. 81 #6, pg. 82 #17" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 3 "# 6" }} {PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 331 "The firs t problem (#6) was a mixing problem. The air in a small room 12ft by \+ 8ft is 3% carbon monoxide. Starting at t=0, freah air containing no c arbon monoxide is blown into the room at a rate of 100 ft^3/min. If a ir in the room flows out through a vent at the same rate, when will th e air in the room be 0.01% carbon monoxide?" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 391 "We figure our in flow rate to \+ be 0, Our rate was 100 ft^3/min *( x(t) kg / 768 ft^3). Our final DE \+ was dx/dt=(-100/768) * x. We said that the equation was separable. W e solved out our DE to t=-768/100 * ln(x) + c, with the initial condit ion X(0) = 23.04. Our c = 24.09. Using this information we anted to \+ know at what t obtained a mix of 0.0768 kg. Algebraicly we solved t = 43.8 mins." }}{PARA 0 "" 0 "" {TEXT -1 2 " " }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 8 "restart:" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 35 "equ1:=diff(x(t),t)=(-100/768)*x(t);" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%%equ1G/-%%diffG6$-%\"xG6#%\"tGF,,$F)#!#D\"$#>" }}} {EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 37 "sol:=dsolve(\{equ1, x(0)=23. 04\},x(t));" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%$solG/-%\"xG6#%\"tG,$ -%$expG6#,$F)#!#D\"$#>$\"++++/B!\")" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 25 "solve(rhs(sol)=.0768,t); " }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+T\\]!Q%!\")" }}}{EXCHG {PARA 0 "" 0 "" {TEXT -1 115 "By hand and by maple it takes 43.8 mins to get the room down to t he desried concentration of 0.01% carbon monoxide." }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 3 "#17" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 424 "The initail mass of a certain species of fish is 7 million tons. \+ The mass of fish, if left alone, would increase at a rate proportiona l to the mass, with a proportionality constant of 2/year. However, co mmercial fishing removes fish at a constant rate of 15 million tons pe r year. When will all the fish be gone? If the fishing rate is chang ed so that the initial mass of fish remains constant, what should that rate be?" }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}{PARA 0 "" 0 "" {TEXT -1 551 "It told us 2/year therefore dm/dt= 2m, but then we are told that the fishermen take 15 million per year. Therefore our final DE is 2m -15. This was separable and we got it down to c+t=.5*ln(2m-15). Our \+ initial condition m(0) =7 million, therefore our constant equals 0. F or the second part our DE was 2m-d for d being a variable that makes t he population constant. When solving down our new DE, dm/dt=2m-d, we \+ see (14-d)*e^2t=(14-d). We see the oly d that could make this true is 14. Therefore the answer for the second part is 14 million tons." }} {PARA 0 "" 0 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 8 "restart:" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 30 "equ2:=diff (m(t),t) =2*m(t)-15;" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%%equ2G/-%%di ffG6$-%\"mG6#%\"tGF,,&F)\"\"#!#:\"\"\"" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 35 "sol2:=dsolve(\{equ2, m(0)=7\}, m(t));" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%%sol2G/-%\"mG6#%\"tG,&#\"#:\"\"#\"\"\"-%$expG6#, $F)F-#!\"\"F-" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 28 "evalf(solv e(rhs(sol2)=0,t));" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#$\"+,^-a8!\"*" } }}{EXCHG {PARA 0 "" 0 "" {TEXT -1 101 "Therefore for the first part we got the same answer with maple that we got by hand to be 1.354 years. " }}{PARA 0 "" 0 "" {TEXT -1 0 "" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 29 "equ3:=diff(m(t), t)=2*m(t)-d;" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%%equ3G/-%%diffG6$-%\"mG6#%\"tGF,,&F)\"\"#%\"dG!\"\"" }}}{EXCHG {PARA 0 "> " 0 "" {MPLTEXT 1 0 35 "sol3:=dsolve(\{equ3, m(0) =7\}, m(t));" }}{PARA 11 "" 1 "" {XPPMATH 20 "6#>%%sol3G/-%\"mG6#%\"tG ,&%\"dG#\"\"\"\"\"#*&-%$expG6#,$F)F.F-,&F+#!\"\"F.\"\"(F-F-F-" }}} {EXCHG {PARA 0 "" 0 "" {TEXT -1 104 "From here we saw as written above that d must equal 14 for the population to stay constant at 7 million ." }}}}{MARK "13 0 0" 104 }{VIEWOPTS 1 1 0 1 1 1803 }