# Polynomial equation solve problems

Polynomial equation equation solve

### #1 KingVsGaramja

KingVsGaramja

Newbie

• Members
• 1 posts

• Calculators:
Casio Fx-991EX Classwiz
Casio 4500PA
Casio Fx-991ES

Posted 13 February 2017 - 04:25 AM

Hi friends,

Today i have problems in equation solve. I have casio fx 991EX classwiz, and i have this equation:

x3-2x2-4x+8=0

But when i am going to solve this equation on my calculator it give me only X1 and X2 value why it don't give me the X3 value??????

### #2 pan.gejt

pan.gejt

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• Gender:Male
• Location:CZ

• Calculators:
fx-880, fx-6300G, fx-9700GE, fx-9860G Slim, Classpad 330-A, TI-Nspire + keypad, TI-Nspire CAS, TI-Nspire CX CAS,TI-89 Titanium, HP-50g, SEC-101, fx-991ES PLUS, fx-991DE PLUS, fx-CP400, Canon X MARK I PRO, Citizen SRP-75,

Posted 13 February 2017 - 10:16 AM

Well, the cubic equation has 2 possible situations

- one real root and two complex roots, e.g. x^3+1=0

- three real roots

- all roots are different

e.g. x^3-4x^2-7x+10=0

- single solution, all roots are the same

e.g. x^3-3x^2+3x-1=0

- two distinctive solutions, one root is different and two roots are the same (the equation has two roots)

e.g. your equation has two roots, x1=-2 and x2=x3=2

Your calc has QR code button (shift + optn). If you have android powered phone or tablet with camera and available internet connection, you can see the graph of your equation.

You need only this app