A)(1-x)la 2 +(x+1)la 2-(2x+1)(x-1)
b)(2x-3y)la2+(2x+3y)(2x-3y)
c)(2x+3y)la2+4x(3x-2)+(2x-1)la 2
d)(3a+2b)la2+(2a+b)(2a-b)-(3a-b)la2
e)(3x-1)(3x+1)-(3x+4)la2+2(3x-1)la2
g)(4x-3)la2-3(x-1)-2(2x-7)la2
f)(3-2x)la2-(2x+5)(2x-5)+4(x-2)la2.
va rog ajutor

2
Trebuie sa folosesti formula (a+b)^2=a^2+2ab+b^2
(a-b)^2=a^2-2ab+b^2,si apoi reduci termenii
si (a-b)(a+b)=a^2-b^2
poti faci mai degraba o sa ma prind

Răspunsuri

2014-03-20T20:16:03+02:00
1..1-2x+x^2+x^2+2x+1-(2x^2-2x+x-1)=1+2x^2 +1-2x^2+2x-x+1=x+3...la celelalte se face la fel

La scoala nu ti s-a predat formulele alea?
da dar eu nu o inteleg pe asta cam de lok
Nu intelegi formula sau rezolvarea?
rezolvarea
Pai....(1-x)la2.....in cazul asta,a=1 si b=x
Si folosesi formula (a-b)la2=a^2-2ab+b^2,si acum inlocuiesit.Deci o sa ai :1^2-2*1*x+x^2=1-2x+x^2..Si asa faci si la celelalte
2014-03-20T20:32:05+02:00
A.(1-x)²+(x+1)²-(2x+1)(x+1)=1-2x+x²+x²+2x+1-2x²-2x-x-1=se reduc -2x cu+2x si - 2x²cu +2x²⇒1-3x
b.(2x-3y)²+(2x+3y)(2x-3y)=4x²-6xy-6xy+9y²+4x²-6xy+6xy-9y²=se reduc -6xy cu +6xy si -9y²cu+9y²⇒8x²-12xy=4x(2x-3y)
c.(2x+3y)²+4x(3x-2)+(2x-1)²=4x²+6xy+9y²+12x²-8x+4x²-4x+1=20x²+6xy+9y²-12x+1=3y(2x+3y)+20x²-12x+1=3y(2x+3y)+(x-1/2)(x+1/2)
d.(3a+2b)²+(2a+b)(2a-b)-(3a-b)²=9a²+12ab+4b²+4a²-2ab+2ab-b²-9a²+6ab-b²=18ab+4a²+2b²=2(2a²+9ab+b²)
e.(3x-1)(3x+1)-(3x+4)²+2(3x-1)²=9x²+3x-3x-1-9x²-12x-12x-16+18X²-12x+2=18x²-36x-17
asa se rezolva si urmatoarele -desfaci parantezele, reduci termeni si aduci la forma cea mai simpla
verifica, poate pe undeva s-au mai strecurat mici greseli de calcul dar in principiu asa se rezolva
bafta
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