Ma puteti ajuta va rog frumos :

1} a)reduceti termeni asemenea in expresia: 2(x-y+3)-3(y-x+1)+(+2y-3x)

b)efectuati calculele in expresia:(x+2)(x-3)

c)efectuati calcule in expresia:(8x²-40x³+28x²):(4x²)-2(x+2)

2} a)Calculand: (√2+√3²)

b)Calculand:(√11+√7)(√11-√7)

c)Efectuati: (√2-1)²-2(√3-1)(√3+1)+(2√2+1)²

1

Răspunsuri

2014-04-14T16:09:07+03:00
2(x-y+3)-3(y-x+1)+(+2y-3x)
2x-2y+6-3y+3x-3+2y-3x - ii grupam acum
2x+3x-3x-2y-3y+2y+6-3 -  se reduc +3x cu -3x SI -2y cu +2y
2x-3y-3

========================
(x+2)(x-3)=
x^2-3x+2x-6=
x^2-x+6
===============
(8x²-40x³+28x²):(4x²)-2(x+2)
8x^2:4x^2-40x^3:4x^2+28x^2:4x^2-2(x+2)=
2-10x+7-2(x+2)
2-10x+7-2x-4=
2+7-4-10x-2x=
5-12x
===========================
(√2+√3)^2=
r2^2+2*r2*r3+r3^2=
2+2r6+3=
5+2r6
=====================
(√11+√7)(√11-√7)=
r11^2-r7^2 - aici e o formula
11-7=4
========================
(√2-1)²-2(√3-1)(√3+1)+(2√2+1)²
2-2r2+1-2(3-1)+8+4r2+1=
2-2r2+1-6+2+8+4r2+1=
2+1-6+2+8+1-2r2+4r2=
8-2r2+4r2=
2(4-r2+2r2)
==============
^ inseamna la putere
* inseamna inmultire
r inseamna radical
1 5 1