:а) x(2x^2-3x+1)+2x(3+2x-x^2) б) m(m^2-mn+n^2)-n(m^2+mn+n^2) в) 2p(1-p-3p^2)-3p(2-p-2p^2) г) 2c(5a-3c^2)-c(a-6c^2)+3a(a-c)

а.) x^2+7x

б.)m^3-2m^2n-n^3

в.)p^2-4p

г.) 3a^2+6ac

а) x(2x^2-3x+1)+2x(3+2x-x^2)= 2x^3-3x^2 +x + 6x+4x^2 -2x^3= x^2 +7x = x(x+7)

б) m(m^2-mn+n^2)-n(m^2+mn+n^2)= m^3 -nm^2  +mn^2 -nm^2 -mn^2 -n^3 = m^3-2nm^2 - n^3

в) 2p(1-p-3p^2)-3p(2-p-2p^2)= 2p-2p^2 -6p^3 -6p+3p^2+6p^3 = p^2 -4p = p(p-4)

г) 2c(5a-3c^2)-c(a-6c^2)+3a(a-c)= 10ac- 6c^3-ac+6c^3 +3a^2 -3ac = 3a^2 +6ac= 3a(a+2c)