4a^2-9y^2 : (2x-3y)^2 3xy 6yx 9a^+6a+b^2 . 3b 12ab 3a+b 10c . 10c+4d 25c^2+20cd+4d^2 15cd a^3-b^3 . a 2ab 7a-7b
1. 4a^2-9y^2 : (2x-3y)^2 = (2х-3у)(2х+3у)*6ху = 2(2х+3у) 3xy 6yx 3ху*(2х-3у)^2 2х-3у 9a^+6a+b^2 . 3b = (3а+b)^2*3b = 3a+b 12ab 3a+b 12ab*(3a+b) 4a 10c . 10c+4d = 10c*2(5c+2d)__ = 4_______ 25c^2+20cd+4d^2 15cd (5c+2d)^2*15cd 3d(5c+2d) a^3-b^3 . a = (a-b)(a^2+ab+b^2) * a = a^2+ab+b^2 2ab 7a-7b 2ab * 7(a-b) 14b