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Hi, ?:

Can HP Prime Solve this!

for two equations together find one answer!

X**3+9X**2Y=10
Y**3+XY**2=2

can someone tell me is this a possible or not.
I have tried in all the solvers and have come up with only single answers for both equations separately.
Thank You.

Hope everyone is safe in these trying times.

Maybe the people here didn’t answer because they think you should have found by yourself.
Did you really try on a Prime?

You can find the numeric solutions in CAS view, using fsolve([eq1 eq2], [x y])
I let you do that, I give you the graphic view (green plan is z=10, eq2 is multiplied by 5 to see the intersections of eq1, eq2, z=10)

Best,
Aries

tom234, did you try CAS command solve?


BTW how is previous post relevant to "Can HP Prime Solve..?" is beyond me. In addition, the shown result is considerably incomplete.

(05-11-2020 09:37 AM)chromos Wrote: [ -> ]tom234, did you try CAS command solve?

Code:

solve([(x^3+9*x^2*y) = 10,(y^3+x*y^2) = 2],[x,y])

BTW how is previous post relevant to "Can HP Prime Solve..?" is beyond me. In addition, the shown result is considered incomplete.

Yes, I am in CAS and this is what it looks like Can it do (A+B)^3 factorials?
Like:

https://www.youtube.com/watch?v=dVs26SSUJSA. That the that's the equation on Youtube can it solve for this?

(05-11-2020 08:59 AM)Aries Wrote: [ -> ]

Best,
Aries

Thats not the answer on the TI

The answer and solve we are looking for is at the end of this video.

https://www.youtube.com/watch?v=dVs26SSUJSA

see equation at start fast forward to see the solution.
can it handle x^3(?) and xy^2(x*y^2)

(05-10-2020 10:55 PM)pinkman Wrote: [ -> ]Maybe the people here didn’t answer because they think you should have found by yourself.
Did you really try on a Prime?

You can find the numeric solutions in CAS view, using fsolve([eq1 eq2], [x y])
I let you do that, I give you the graphic view (green plan is z=10, eq2 is multiplied by 5 to see the intersections of eq1, eq2, z=10)

(05-11-2020 09:37 AM)chromos Wrote: [ -> ]tom234, did you try CAS command solve?

Code:

solve([(x^3+9*x^2*y) = 10,(y^3+x*y^2) = 2],[x,y])

BTW how is previous post relevant to "Can HP Prime Solve..?" is beyond me. In addition, the shown result is considered incomplete.

I think the prime can only handle x^2 and cannot handle x^3 or higher.
Its Algebra:https://www.youtube.com/watch?v=dVs26SSUJSA

?

Hi Tom,

Perhaps the syntax of your entry was incorrect. I entered the 2 equations as in the attached screen shot and got the 1,1 answer from the TI Inspire as well as 2 other solutions (which makes sense for third order equations).

Take care & good luck

[attachment=8434]

(05-11-2020 03:35 PM)swagner53 Wrote: [ -> ]I entered the 2 equations as in the attached screen shot and got the 1,1 answer from the TI Inspire
as well as 2 other solutions (which makes sense for third order equations).

Actually, this is a 9-degree equation, with 3 real and 6 complex solutions

eqn2: y^3 + x*y^2 = 2     → x = (2-y^3)/y^2

eqn1: x^3 + 9*x^2*y = 10, substitute x from above

(8*y^9 - 30*y^6 + 24*y^3 + 8) / y^6 = 10
8*(y^9 - 5*y^6 + 3*y^3 + 1) = 0
8* (y^3 - 1) * ((y^3 - 2)^2 - 5) = 0

y^3 = 1, 2 ± √5
y = 1, φ ,1-φ, w, wφ ,w(1-φ), w², w²φ, w²(1-φ),       where w=exp(i*pi/3), φ=(1+√5)/2

Hi Albert,

You are absolutely correct. I did not have COMPLEX checked in the CAS settings. When I did, the Prime returned all 9 solutions - 3 real and 6 complex.

Thanks, Steve

(05-11-2020 03:35 PM)swagner53 Wrote: [ -> ]Hi Tom,

Perhaps the syntax of your entry was incorrect. I entered the 2 equations as in the attached screen shot and got the 1,1 answer from the TI Inspire as well as 2 other solutions (which makes sense for third order equations).

Take care & good luck

I did exactly what you did and got nothing just empty brackets.

(05-11-2020 05:49 PM)swagner53 Wrote: [ -> ]Hi Albert,

You are absolutely correct. I did not have COMPLEX checked in the CAS settings. When I did, the Prime returned all 9 solutions - 3 real and 6 complex.

Thanks, Steve

I did have complex on!

(05-11-2020 05:49 PM)swagner53 Wrote: [ -> ]Hi Albert,

You are absolutely correct. I did not have COMPLEX checked in the CAS settings. When I did, the Prime returned all 9 solutions - 3 real and 6 complex.

Thanks, Steve

got this is something wrong with this calculator
?

(05-11-2020 05:14 PM)Albert Chan Wrote: [ -> ]

(05-11-2020 03:35 PM)swagner53 Wrote: [ -> ]I entered the 2 equations as in the attached screen shot and got the 1,1 answer from the TI Inspire
as well as 2 other solutions (which makes sense for third order equations).

Actually, this is a 9-degree equation, with 3 real and 6 complex solutions

eqn2: y^3 + x*y^2 = 2     → x = (2-y^3)/y^2

eqn1: x^3 + 9*x^2*y = 10, substitute x from above

(8*y^9 - 30*y^6 + 24*y^3 + 8) / y^6 = 10
8*(y^9 - 5*y^6 + 3*y^3 + 1) = 0
8* (y^3 - 1) * ((y^3 - 2)^2 - 5) = 0

y^3 = 1, 2 ± √5
y = 1, φ ,1-φ, w, wφ ,w(1-φ), w², w²φ, w²(1-φ),       where w=exp(i*pi/3), φ=(1+√5)/2

got this is something wrong with this calculator
?

Try putting braces around the two equations, as in a list.

Also, you are using "xy" in the equations, and probably need to specify "x*y", but I'm no Prime expert and maybe implicit multiplication is allowed in some places?

(05-11-2020 12:37 PM)tom234 Wrote: [ -> ]

(05-11-2020 09:37 AM)chromos Wrote: [ -> ]tom234, did you try CAS command solve?

Code:

solve([(x^3+9*x^2*y) = 10,(y^3+x*y^2) = 2],[x,y])

BTW how is previous post relevant to "Can HP Prime Solve..?" is beyond me. In addition, the shown result is considered incomplete.

I think the prime can only handle x^2 and cannot handle x^3 or higher.
Its Algebra:https://www.youtube.com/watch?v=dVs26SSUJSA

?

Thank you after several tries at this I put the calculator into Algebraic mode and entered your formula above the way you did above.
The blue key bracks were Matrix in Textbook mode however, in Algebraic mode they were square [] the answers you got were now what I got and what the video got.

I have to say there was no way to get square brackets in text mode.

The answer you got was for me in Algebraic mode in Cas solve.

(05-11-2020 09:37 AM)chromos Wrote: [ -> ]tom234, did you try CAS command solve?

Code:

solve([(x^3+9*x^2*y) = 10,(y^3+x*y^2) = 2],[x,y])

BTW how is previous post relevant to "Can HP Prime Solve..?" is beyond me. In addition, the shown result is considered incomplete.

This has been a day-long problem. I was ready to send it back.
1. I reset the Virtual HP Prime on the computer and got some better answer.(in Text Mode).
2. I reformated my C drive on the HP Prime calculator.
3. The final thing is I change to Algebraic mode and entered it as you all suggested.
That when the answer in all the fractions and the 1,1 was realized.
4. Remember I said I could not get it in CAS Solve (Text MOde) I just switched it and it came back with the same right answer. How is this possible is this thing possessed.
or what? Hell, that's some kind of crazy.

Numerical and symbolic solve. Still don’t understand what’s wrong.
[attachment=8438]