a) =6x
b)=0
c)=2√3
d)=-abc
3)
a)=21x
b)=-93xy
c)=x²y²
d)=-2√9x²y²=-6x²y²
4)
a)=2x-2-3x+6=4-5x
b)=2x²-x-2x²=-x
c)=5x-5-10x=-5x-5=-5(x+1)
d)=4x²-x-4x²=-x
e)=x²+xy-x²=xy
f)=5x²+5x
g)=2x²-x+14x-7-2x²=13x-7
h)=6x²-2-x²-x=5x²-x-2
i)=x²+x-2x-2-x²+3x=2x-2=2(x-1)
5)
a)=3(x+y)
b)=2(2x+3y)
c)=15x²/3=5x²
d)=4√2xyz
6)
P=perimetru (lungimea gardului)
L=lungimea
l=latimea
A=aria(suprafata)
l=2x+3-2x=3
P=2(L+l)
d) P=2(2x+3+3)=2(2x+6)=4x+12
e) A=Lxl=(2x+3)*3=6x+9
7) P=4a(a+b)
P=4xL
L=P:4=4a(a+b):4=a(a+b)
A=L²=[a(a+b)]²=a²(a+b)²=a²(a²+2ab+b²)=a⁴+2a³b+a²b²
8)
a)= 4x²:4x³+2x²+3x-2x-3=1/x+2x²+x-3=(1+2x³+x²-3x)/x
b)=-x¹⁵:x¹²+3x⁴y/5:(-x²y/5)+(3/x)²=-x³-3x²+9/x²=(-x⁵-3x⁴+9)/x²
c)=-8x²y(3x+xy³):(-8x²y)-3x=3x+xy³-3x=xy³
9)
i)
a=(x+3)²=x²+6x+9
b=(xy+2)²=x²y²+4xy+4
c)=a²+4axy+4x²y²
d)=16a²+24ay+9y²
ii)
a) =x²-6x+9
b)=4x²-12xy+9y²
c)=25x²-40xy+16y²
d)=4a²-12axy+9x²y²
iii)
a)=3²-x²=9-x²
b)=4a²-b²
c)=16x²-4y²
iv)
a=√3²-x²=3-x²
b)=-(5by-2ax)(5by-2ax)=-(25b²y²-4a²x²)=4a²x²-25b²y²
c)=(4-x²)(4+x²)=16-x⁴
Sper ca nu am gresit pe la calcule si tia-m fost de folos
