S = <span>13,6+ 10,4 + 10,8 + 14,4 = </span>49,2
n = 4
Se = S/n = 49,2/4 = 12,3
1.
a) 5^2*5^3=5^5
b)8^8:8^3=8^(8-3)=8^5
w)(b^4)^5=b^20
g)3^7*4*7=(3*4)^7
2.
(3x^3y-4xy^2-2y)-(2x^3y+6xy^2-y)=
=3x^3y-4xy^-2y-2x^3y-6xy^2+y=
=x^3y-10xy^2-y
3.
A(2a^2b^3c)*(-3,5a^3bc^3)=
=-7a^5b^4c^4
b) (Sn-1/4p)(1/4p+Sn)=
=(Sn-1/4p)(Sn+1/4p)=
=(Sn)^2 – 1/16p^2
4.
A=-2x^3y-1,5xy^2
A=-2(1,5)^3*(-2) – 1,5(1,5)*(-2)^2
A=4*3,375-2,25*4
A=4(3,375-2,25)
A=4*1,125
A=4,5
B=-0,4x^3y+1,5xy^2
B=-0,4(1,5^3*(-2)+1,5(1,5)*(-2)^2
B=-0,4*3,375*(-2)+2,25*4
B=-1,35*(-2)+9
B=2,7+9
B=11,7
5.
2(x+3)(x-2)-(2x+1)(x-3)-7=0
2x^2-4x+6x-12-(2x^2-6x+x-3)-7
2x^2+2x-19-2x^2+6x-x+3=0
7x-16=0
7x=16 // : 7
<span>р^2х+рх^2 = px (p+x)
</span><span>2ас-4аbc = 2ac (1 - 2b)
</span>
<span>3x^2+3x^3y = 3x^2 (1 + xy)
</span>
<span>6a^2b+3ab^2 = 3ab (2a + b)</span>
