topic Re: No solution was found in PTC Mathcad
https://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732570#M196163
<P>I'm constrained to Prime Express, since I don't have a license. (Express is free!) Symbolic operations (like solve) are "premium" features that Express will display but not execute, so I can see what you've done (as long as I don't resave your sheet) but I can't run it.</P>
<P> </P>
<P>That said, symbolic operations never were a really strong feature in Mathcad and they have not improved in Prime. The numeric solution shows that the derivative function goes strongly positive for negative x, change the range of xx to see this. The derivative function goes to zero at x = 0, but it does not go negative until x = 3/4. So the root function (which Express will do) cannot find the root at zero, but it will find the root at 3/4. I suspect that the solve found a double root at zero because of two imaginary roots.</P>Sat, 05 Jun 2021 19:37:53 GMTFred_Kohlhepp2021-06-05T19:37:53ZNo solution was found
https://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732564#M196159
<P>Hi, im totally newbie.</P>
<P>I have 2 problems and i dont know hot to solve it <span class="lia-unicode-emoji" title=":confused_face:">ðŸ˜•</span></P>
<P> </P>
<P>Any ideas ?</P>Sat, 05 Jun 2021 17:37:35 GMThttps://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732564#M196159MK_99526842021-06-05T17:37:35ZRe: No solution was found
https://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732565#M196160
<P>I can't do symbolics, but I can address your issues:</P>Sat, 05 Jun 2021 17:55:08 GMThttps://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732565#M196160Fred_Kohlhepp2021-06-05T17:55:08ZRe: No solution was found
https://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732566#M196161
<P>is this the only one solution? <SPAN>you can't solve the inequality with the "solve" method?</SPAN></P>Sat, 05 Jun 2021 18:10:45 GMThttps://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732566#M196161MK_99526842021-06-05T18:10:45ZRe: No solution was found
https://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732570#M196163
<P>I'm constrained to Prime Express, since I don't have a license. (Express is free!) Symbolic operations (like solve) are "premium" features that Express will display but not execute, so I can see what you've done (as long as I don't resave your sheet) but I can't run it.</P>
<P> </P>
<P>That said, symbolic operations never were a really strong feature in Mathcad and they have not improved in Prime. The numeric solution shows that the derivative function goes strongly positive for negative x, change the range of xx to see this. The derivative function goes to zero at x = 0, but it does not go negative until x = 3/4. So the root function (which Express will do) cannot find the root at zero, but it will find the root at 3/4. I suspect that the solve found a double root at zero because of two imaginary roots.</P>Sat, 05 Jun 2021 19:37:53 GMThttps://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732570#M196163Fred_Kohlhepp2021-06-05T19:37:53ZRe: No solution was found
https://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732583#M196165
<P>Page 2 Triple root is 0 and the f(0) = 0 with evaluate "=". </P>
<P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="image.png" style="width: 310px;"><img src="https://community.ptc.com/t5/image/serverpage/image-id/42462i9EC52DA223B383AD/image-size/large?v=v2&px=999" role="button" title="image.png" alt="image.png" /></span><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="image.png" style="width: 136px;"><img src="https://community.ptc.com/t5/image/serverpage/image-id/42463i9B88691F7F87F6C4/image-size/large?v=v2&px=999" role="button" title="image.png" alt="image.png" /></span></P>
<P>Page 4 df(x) must above the plot.</P>
<P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="image.png" style="width: 382px;"><img src="https://community.ptc.com/t5/image/serverpage/image-id/42464iBB106554BF3D0580/image-size/large?v=v2&px=999" role="button" title="image.png" alt="image.png" /></span><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="image.png" style="width: 708px;"><img src="https://community.ptc.com/t5/image/serverpage/image-id/42465iC04AC50BFA1AFA0B/image-size/large?v=v2&px=999" role="button" title="image.png" alt="image.png" /></span></P>Sat, 05 Jun 2021 23:46:20 GMThttps://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732583#M196165ttokoro2021-06-05T23:46:20ZRe: No solution was found
https://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732597#M196168
<P>The inequality:</P>
<P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="LucMeekes_1-1622971273434.png" style="width: 400px;"><img src="https://community.ptc.com/t5/image/serverpage/image-id/42475iF4437324AE0C5AF3/image-size/medium?v=v2&px=400" role="button" title="LucMeekes_1-1622971273434.png" alt="LucMeekes_1-1622971273434.png" /></span></P>
<P>This means: x<0 OR 0<x<3/4</P>
<P> </P>
<P>Success!<BR />Luc</P>
<P> </P>Sun, 06 Jun 2021 09:22:16 GMThttps://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732597#M196168LucMeekes2021-06-06T09:22:16ZRe: No solution was found
https://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732600#M196169
<BLOCKQUOTE><HR /><LI-USER uid="14826"></LI-USER> wrote:<BR />
<P>The inequality:</P>
<P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="LucMeekes_1-1622971273434.png" style="width: 400px;"><img src="https://community.ptc.com/t5/image/serverpage/image-id/42475iF4437324AE0C5AF3/image-size/medium?v=v2&px=400" role="button" title="LucMeekes_1-1622971273434.png" alt="LucMeekes_1-1622971273434.png" /></span></P>
<P>This means: x<0 OR 0<x<3/4</P>
<P> </P>
<P>Success!<BR />Luc</P>
<P> </P>
<HR /></BLOCKQUOTE>
<P>What you show is the result of MC11 with Maple as symbolic engine. Unfortunately the symbolic engine was changed twice since then and the newest one (Axiom/FriCAS; the only one available in Prime 7) is not able to solve that inequality.</P>
<P>Here is a comparison done in Prime 6 showing of the results we get using the legacy symbolic (muPad) and the new one (Axiom/FriCAS). Interesting in both cases is the effects we get, when we simply use "solve" compared to those <SPAN class="VIiyi"><SPAN class="JLqJ4b ChMk0b" data-language-for-alternatives="en" data-language-to-translate-into="de" data-phrase-index="0"><SPAN>if we explicitly specify the variable</SPAN></SPAN></SPAN> x. <SPAN class="VIiyi"><SPAN class="JLqJ4b ChMk0b" data-language-for-alternatives="en" data-language-to-translate-into="de" data-phrase-index="0"><SPAN>There is also a big difference in the results depending on whether we are storing the derivative into a function or using it directly.</SPAN></SPAN></SPAN> Also note the effect "simplify" has on the result with the new symbolic.</P>
<P> </P>
<P>Legacy Symbolic (muPad):</P>
<P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="Werner_E_0-1622975120223.png" style="width: 999px;"><img src="https://community.ptc.com/t5/image/serverpage/image-id/42476i86E4859937C0FB0D/image-size/large?v=v2&px=999" role="button" title="Werner_E_0-1622975120223.png" alt="Werner_E_0-1622975120223.png" /></span></P>
<P> </P>
<P>New symbolic (Axiom/FriCAS):</P>
<P><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="Werner_E_1-1622975160951.png" style="width: 999px;"><img src="https://community.ptc.com/t5/image/serverpage/image-id/42477i657F5E1DC90CE1F5/image-size/large?v=v2&px=999" role="button" title="Werner_E_1-1622975160951.png" alt="Werner_E_1-1622975160951.png" /></span></P>
<P> </P>
<P> </P>Sun, 06 Jun 2021 10:29:56 GMThttps://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732600#M196169Werner_E2021-06-06T10:29:56ZRe: No solution was found
https://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732604#M196171
<P><SPAN class="VIiyi"><SPAN class="JLqJ4b ChMk0b" data-language-for-alternatives="en" data-language-to-translate-into="de" data-phrase-index="0"><SPAN>As described above, the new and only symbolic available in P7 is unable to solve this inequality.</SPAN></SPAN></SPAN></P>
<P> </P>
<P>According to plotting:</P>
<P>It works OK, if you either</P>
<UL>
<LI>define a function for the derivative<BR /><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="Werner_E_0-1622975880213.png" style="width: 400px;"><img src="https://community.ptc.com/t5/image/serverpage/image-id/42478i736A372495F7392C/image-size/medium?v=v2&px=400" role="button" title="Werner_E_0-1622975880213.png" alt="Werner_E_0-1622975880213.png" /></span></LI>
<LI>or if you define a range variable<BR /><span class="lia-inline-image-display-wrapper lia-image-align-inline" image-alt="Werner_E_1-1622975949590.png" style="width: 400px;"><img src="https://community.ptc.com/t5/image/serverpage/image-id/42479i189917D7F1E6A546/image-size/medium?v=v2&px=400" role="button" title="Werner_E_1-1622975949590.png" alt="Werner_E_1-1622975949590.png" /></span></LI>
</UL>
<P>I manually changed the lower limit on the abscissa to -1 in the first plot (quickplot) and in both cases the upper limit on the ordinate to 0.2.</P>Sun, 06 Jun 2021 10:44:56 GMThttps://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732604#M196171Werner_E2021-06-06T10:44:56ZRe: No solution was found
https://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732605#M196172
<P>Thank you! You helped me a lot. All of you. Greetings! </P>Sun, 06 Jun 2021 14:07:40 GMThttps://community.ptc.com/t5/PTC-Mathcad/No-solution-was-found/m-p/732605#M196172MK_99526842021-06-06T14:07:40Z