a) m²n+mn²-3m-3n=
б) x³-125=
в)y³+64=

a) (2a+3)-4a-(3a-5)²=
б)3(x+6)-(x-6) (x+6)=
в)(m-4),(m+3)-m²=

a) 12c²-12d²=
б)-m²+8m-16=
в)ax³-ay³=
г)в²c⁴-c²b⁴=

y(y+7) (y-3)=y²(y-2)=

a)

m²n+mn²-3m-3n=  mn(m+n) - 3(m+n) = (m + n)(mn - 3),

б)

x³-125=  (x-5)(x²+5*x+5²) = (x - 5)(x² + 5x + 25),

в)

y³+64=  (y+4)(y²-4*y+4²) = (y + 4)(y² - 4y + 16),

a)

(2a+3)-4a-(3a-5)²=  2а+3-4а-9а²+30а-25 = -9а² + 28а - 22,

б)

3(x+6)-(x-6) (x+6)=  3х+18-х²+36 = -х² + 3х + 54,

в)

(m-4)(m+3)-m²=  m²+3m-4m-12-m² = -m - 12,

a)

12c²-12d²=  12*(c²-d²) = 12*(c - d)(c + d),

б)

-m²+8m-16=  -(m²-8m+16) = -(m - 4)²,

в)

ax³-ay³=  a*(x³-y³) = a*(x - y)(x² + xy + y²),

г)

b²c⁴-c²b⁴=  b²c²*(c²-b²) = b²c²*(c - b)(c + b),

y(y+7) (y-3) = y²(y-2).

у(у²-3у+7у-21) = у³-2у²,

у³ - 3у² + 7у² - 21у - у³ + 2у² = 0,

6у² - 21у = 0,

у * (6у - 21) = 0,

у1 = 0,    6у - 21 = 0,

              6у = 21,

              у2 = 3,5