4t ESO/4.05 INEQUACIONS/4.05.2 Signe d'una expressió algèbrica 4.05.2.41Q Resol ax^2+bx+c Negatiu Resol: #e < 0

Format de la resposta:

Entre dos nombres: «math xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mn»2«/mn»«mo»§lt;«/mo»«mi»x«/mi»«mo»§#8743;«/mo»«mi»x«/mi»«mo»§lt;«/mo»«mn»5«/mn»«mo»§#160;«/mo»«mo»§#160;«/mo»«mo»§#160;«/mo»«mo»§#160;«/mo»«mo»(«/mo»«mo»§#8743;«/mo»«mo»=«/mo»«mi»i«/mi»«mo»)«/mo»«/math»

Altra situació: «math xmlns=¨http://www.w3.org/1998/Math/MathML¨»«mi»x«/mi»«mo»§lt;«/mo»«mo»-«/mo»«mn»2«/mn»«mo»§#8744;«/mo»«mi»x«/mi»«mo»§#62;«/mo»«mn»5«/mn»«mo»§#160;«/mo»«mo»§#160;«/mo»«mo»§#160;«/mo»«mo»§#160;«/mo»«mo»(«/mo»«mo»§#8744;«/mo»«mo»=«/mo»«mi»o«/mi»«mo»)«/mo»«/math»

]]> 1.0000000 0.3333333 0 0 #sol

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name="imaginary_unit">i</option></options><localData><data name="inputField">popupEditor</data><data name="gradeCompound">and</data><data name="gradeCompoundDistribution"></data><data name="casSession"/></localData></question> Primer es resol l'equació de 2n grau.

el discriminant és #d i les solucions són #x_1 i #x_2.

(ES COMPROVEN AMB S = #S1 I P = #P1)

Després es fa la taula.

]]> Si fem la taula:

Com que a és #r1,

#e és #r2 (signe de a), #r4, per x<#x_1 o per x>#x_2

#e és #r3 (signe contrari de a), #r5, per #x_1<x i per x<#x_2

.oo

#x_1

#x_2

+oo

#s1

#s2

#s1

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