28.
1) a(b-2)/5(b-2)=a/5( b-2 сокращаем сверху и снизу)
2)3(x+4)/c(x+4)=3/c
3)ab(y+3)/a^2b(y+3)=ab/a^2b=1/a
4)15a(a-b)/20b(a-b)=15a/20b=3a/ 4b
29.
1)3a+12b/6ab=3(a+4b)/6ab=a+4b/ 2ab
3)2a-4/3(a-2)=2(a-2)/3(a-2)=2/3
5)a-3b/a^2-3ab=a-3b/a(a-3b)=1/ a
2)15b-20c/10b=5(3b-4c)/10b=3b-4c/ 2b
4)5x(y+2)/6y+12=5x(y+2)/6(y+2)=5x/ 6
6)3x^2+15xy/x+5y=3x(x+5y)/x+5y=3x
30.
1)y^2-16/3y+12=(y-4)(y+4)/3(y+4)=y-4/ 3
2)5x-15y/x^2-9y^2=5(x-3y)/(x-3y)(x+3y)=5/ x+3y
3)(c+2)^2/7c^2+14c=(c+2)^2/7c(c+2)=c+2/ 7c
4)6cd-18c/(d-3)^2=6c(d-3)/(d-3)^2=6c/ d-3
5)a^2+10a+25/a^2-25=(a+5)^2/(a-5)(a+5)==a+5/ a-5
6)y^2-9/y^2-6y+9=(y-3)(y+3)/(y-3)^2=y+3/ y-3
(/-дробь)
Ответ:
Объяснение:
2. a) ab-c
b) n^3+m^3
3. a) 19c
б) 2,6c
в) =65-56x+35=100-56x
г) = -80x+40+80x=40
д) = -18b-60+30c+60+15c-2b= -20b+45c
е) = 5d-d-9-d= 3d-9
5x-4y=8|*-3⇒-15x+12y=-24
15x-12y=20
0=-4
решения нет
=log1/2(корень из 3)-log1/2(3)=1/2 log1/2(3)- log1/2(3)=- 1/2 log1/2(3)
А) -4.5+(-5.6+4.5)=-4.5-1.1=5.6 б)-4.5-(-5.6-4.5)=-4.5-11=15.5