№8
1
б и в
2
а)а²-b²
б)36-x²
в)9-6y+y²
3
а)9n²+12n+4
б)4/25+m²-4/7*mn+25/49*n²
4
а)4-20y+25y²+3=16y²-24y+9-4+9y²
-20y+25y²-25y²+24y=5-7
4y=-2
y=-0,5
б)9x²-42x+49+9x²+42x+49=116
18x²=116-98
18x²=18
x²=1
x=1 U x=-1
5
а)(4000+2)(4000-2)=16000000-4=15999996
б)(5+2/7)(5-2/7)=25-4/49=24 45/49
6
а)1-3x+3x²-x³-1-3x-3x²-x³+2x³=36
-6x=36
x=36:(-6)
x=-6
б)y³-8-y(y²-9)=1
y³-8-y³+9y=1
9y=1+8
9y=9
y=1
№9
1
б и г
2
а)5(a+b)
б)7n(m-k)
в)x^4*(4x+2x²-1)
3
3a²b²(b²-6a^5b³+4a^8)
4
x²(x+12)-(x+12)=0
(x+12)(x²-1)=0
(x+12)(x-1)(x+1)=0
x=-12 x=1 x=-1
5
a)6^46*(6-1)/(36*5)=6^46*5/(6²*5)=6^44
б)12^21*(13²+13+1)/61=13^21*(169+13+1)/61=13^(21*183/61=3*13^21