Please Help !!! - Problem in Plot
- To: mathgroup@smc.vnet.net
- Subject: [mg11600] Please Help !!! - Problem in Plot
- From: Jae Sung Lee <jslee@kuccnx.korea.ac.kr>
- Date: Tue, 17 Mar 1998 10:43:34 -0500
- Organization: System Engineering Research Institute (SERI)
I am to solve the following formula ; soln1=Solve[x*(1-x)^(z-2)==y*(1-y)^(z-2), x] where z = 6, and it is expected that x is the function of y. and got the following six solutions ; Out[]= ({{x -> y}, { x -> (4 - y)/4 - 1/2[Sqrt](( ( - 6) + 1/4(((-4) + y))^2 + 4 y - y^2 + 1/3((6 - 4 y + y^2)) + ((2*2^(1/3)(((-1) + y))^2 y(((-6) + 5 y) )))/((3(((-45) y^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^\((1/3)\))\) + \(1\/\(3\ 2\^\(1/3\)\)\(( \((\(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^\((1/3)\))\)\))\) - 1\/2\ \[Sqrt]\(( \( - 6\) + 1\/2\ \((\(-4\) + y)\)\^2 + 4\ y - y\^2 + 1\/3\ \((\(-6\) + 4\ y - y\^2)\) - \((2\ 2\^\(1/3\)\ \((\(-1\) + y)\)\^2\ y\ \((\(-6\) + 5\ y) \))\)/\(( 3\ \((\(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^\((1/3)\))\) - \(1\/\(3\ 2\^\(1/3\)\)\(( \((\(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^\((1/3)\))\)\) - \((\(-\((\(-4\) + y)\)\^3\) + 4\ \((\(-4\) + y)\)\ \((6 - 4\ y + y\^2)\) - 8\ \((\(-4\) + 6\ y - 4\ y\^2 + y\^3)\))\)/ \((4\ \[Sqrt]\(( \( - 6\) + 1\/4\ \((\(-4\) + y)\)\^2 + 4\ y - y\^2 + 1\/3\ \((6 - 4\ y + y\^2)\) + \((2\ 2\^\(1/3\)\ \((\(-1\) + y)\)\^2\ y\ \(( \(-6\) + 5\ y)\))\)/ \((3\ \(( \(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^ \((1/3)\))\) + \(1\/\(3\ 2\^\(1/3\)\)\(( \((\(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^ \((1/3)\))\)\))\))\))\)}, { x -> (4 - y)/4 - 1\/2\ \[Sqrt]\(( \( - 6\) + 1\/4\ \((\(-4\) + y)\)\^2 + 4\ y - y\^2 + 1\/3\ \((6 - 4\ y + y\^2)\) + \((2\ 2\^\(1/3\)\ \((\(-1\) + y)\)\^2\ y\ \((\(-6\) + 5\ y) \))\)/\(( 3\ \((\(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^\((1/3)\))\) + \(1\/\(3\ 2\^\(1/3\)\)\(( \((\(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^\((1/3)\))\)\))\) + 1\/2\ \[Sqrt]\(( \( - 6\) + 1\/2\ \((\(-4\) + y)\)\^2 + 4\ y - y\^2 + 1\/3\ \((\(-6\) + 4\ y - y\^2)\) - \((2\ 2\^\(1/3\)\ \((\(-1\) + y)\)\^2\ y\ \((\(-6\) + 5\ y) \))\)/\(( 3\ \((\(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^\((1/3)\))\) - \(1\/\(3\ 2\^\(1/3\)\)\(( \((\(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^\((1/3)\))\)\) - \((\(-\((\(-4\) + y)\)\^3\) + 4\ \((\(-4\) + y)\)\ \((6 - 4\ y + y\^2)\) - 8\ \((\(-4\) + 6\ y - 4\ y\^2 + y\^3)\))\)/ \((4\ \[Sqrt]\(( \( - 6\) + 1\/4\ \((\(-4\) + y)\)\^2 + 4\ y - y\^2 + 1\/3\ \((6 - 4\ y + y\^2)\) + \((2\ 2\^\(1/3\)\ \((\(-1\) + y)\)\^2\ y\ \(( \(-6\) + 5\ y)\))\)/ \((3\ \(( \(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^ \((1/3)\))\) + \(1\/\(3\ 2\^\(1/3\)\)\(( \((\(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^ \((1/3)\))\)\))\))\))\)}, { x -> (4 - y\)\/4 + 1\/2\ \[Sqrt]\(( \( - 6\) + 1\/4\ \((\(-4\) + y)\)\^2 + 4\ y - y\^2 + 1\/3\ \((6 - 4\ y + y\^2)\) + \((2\ 2\^\(1/3\)\ \((\(-1\) + y)\)\^2\ y\ \((\(-6\) + 5\ y) \))\)/\(( 3\ \((\(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^\((1/3)\))\) + \(1\/\(3\ 2\^\(1/3\)\)\(( \((\(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^\((1/3)\))\)\))\) - 1\/2\ \[Sqrt]\(( \( - 6\) + 1\/2\ \((\(-4\) + y)\)\^2 + 4\ y - y\^2 + 1\/3\ \((\(-6\) + 4\ y - y\^2)\) - \((2\ 2\^\(1/3\)\ \((\(-1\) + y)\)\^2\ y\ \((\(-6\) + 5\ y) \))\)/\(( 3\ \((\(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^\((1/3)\))\) - \(1\/\(3\ 2\^\(1/3\)\)\(( \((\(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^\((1/3)\))\)\) + \((\(-\((\(-4\) + y)\)\^3\) + 4\ \((\(-4\) + y)\)\ \((6 - 4\ y + y\^2)\) - 8\ \((\(-4\) + 6\ y - 4\ y\^2 + y\^3)\))\)/ \((4\ \[Sqrt]\(( \( - 6\) + 1\/4\ \((\(-4\) + y)\)\^2 + 4\ y - y\^2 + 1\/3\ \((6 - 4\ y + y\^2)\) + \((2\ 2\^\(1/3\)\ \((\(-1\) + y)\)\^2\ y\ \(( \(-6\) + 5\ y)\))\)/ \((3\ \(( \(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^ \((1/3)\))\) + \(1\/\(3\ 2\^\(1/3\)\)\(( \((\(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^ \((1/3)\))\)\))\))\))\)}, { x -> (4 - y\)\/4 + 1\/2\ \[Sqrt]\(( \( - 6\) + 1\/4\ \((\(-4\) + y)\)\^2 + 4\ y - y\^2 + 1\/3\ \((6 - 4\ y + y\^2)\) + \((2\ 2\^\(1/3\)\ \((\(-1\) + y)\)\^2\ y\ \((\(-6\) + 5\ y) \))\)/\(( 3\ \((\(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^\((1/3)\))\) + \(1\/\(3\ 2\^\(1/3\)\)\(( \((\(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^\((1/3)\))\)\))\) + 1\/2\ \[Sqrt]\(( \( - 6\) + 1\/2\ \((\(-4\) + y)\)\^2 + 4\ y - y\^2 + 1\/3\ \((\(-6\) + 4\ y - y\^2)\) - \((2\ 2\^\(1/3\)\ \((\(-1\) + y)\)\^2\ y\ \((\(-6\) + 5\ y) \))\)/ \((3\ \(( \(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^\((1/3)\))\) - \(1\/\(3\ 2\^\(1/3\)\)\(( \((\(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^\((1/3)\))\)\) + \((\(-\((\(-4\) + y)\)\^3\) + 4\ \((\(-4\) + y)\)\ \((6 - 4\ y + y\^2)\) - 8\ \((\(-4\) + 6\ y - 4\ y\^2 + y\^3)\))\)/ \((4\ \[Sqrt]\(( \( - 6\) + 1\/4\ \((\(-4\) + y)\)\^2 + 4\ y - y\^2 + 1\/3\ \((6 - 4\ y + y\^2)\) + \((2\ 2\^\(1/3\)\ \((\(-1\) + y)\)\^2\ y\ \(( \(-6\) + 5\ y)\))\)/ \((3\ \(( \(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^ \((1/3)\))\) + \(1\/\(3\ 2\^\(1/3\)\)\(( \((\(-45\)\ y\^2 + 160\ y\^3 - 210\ y\^4 + 120\ y\^5 - 25\ y\^6 + \[Sqrt]\(( 6912\ y\^3 - 56727\ y\^4 + 207360\ y\^5 - 443340\ y\^6 + 611280\ y\^7 - 563922\ y\^8 + 348192\ y\^9 - 138780\ y\^10 + 32400\ y\^11 - 3375\ y\^12)\))\)^ \((1/3)\))\)\))\))\))\)}}\) I make the pure function R[x], later it should be used in another expression, as follows; R[x_]:=soln1[[2]] /.y->x Problem occurred when I plot this function Plot[R[x], {x,0,1}] Mathematica displays following messages ; Plot::plnr: "R[x] is not a machine-size real number at x = 4.16666666666666607`*^-8 Plot::plnr: R[x] is not a machine-size real number at x = 0.0405669915729157892 Plot::plnr: R[x] is not a machine-size real number at x = 0.0848087998593736713 General::stop: Further output of (Plot :: plnr) will be suppressed during this calculation. and in Front End Message is as follows ****************************************************************************** Front End Message The string '\!\(R[x]\) is not a machine-size real number at x = 4.16666666666666607`*^-8' cannot be displayed with ShowStringCharacters->False due to an error in the string. ****************************************************************************** However, when these values are put into R[x] In[1]:=r[4.16666666666666607`*^-8] Out[1]={x -> 0.985661} In[2]:=r[0.0405669915729157892] Out[2]={x -> 0.4836810121606896} In[3]:=r[0.0848087998593736713] Out[3]={x ->0.3642868596845246} What is the meaning of above Front End Message ? What is wrong? Please help me !!!! Thanks for reading.