An equation that hp prime can't solve

[Carsen]

(02-17-2019 06:14 AM)yangyongkang Wrote:  

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Is this not a BUG? 


I would not jump to the conclusion that it is a "BUG". It is most likely the user's fault due to not understanding the calculator or not entering the input correctly.

I was able to solve this problem using my HP 50g, a calculator I know VERY well. I understand how it works and I know what tools to use. See the screenshot titled "Proof" to see that I actually solved it with my HP 50g.

(02-17-2019 06:14 AM)yangyongkang Wrote:  Hello everyone, I am back. I recently encountered a system of equations, hp prime not only can not solve the exact solution, even the numerical solution can not be solved.

Now, I will help you on how to solve this with your HP Prime.

After playing around with this equation (what a pain to enter in), the problem most likely lies with using a function ( the f(x,y) part) with the differentiate command. The 50g spits out a symbolic answer when I use the DERIV command on the f(x,y). See pictures #1 & #2. But when I attempt this on Prime, I get something I do not understand. See picture #3. So try to derive the function and get a symbolic answer, like my 50g. Maybe then fsolve() will work.

Unfortunately for you, I cannot tell you exactly what to do to get the answer because I am not good at using the HP Prime. That being said, keep working on it and good luck!!