А. (3а+1)^2= (3a)^2 +2*3a*1+1^2= 9a^2 + 6a +1
(a+b)^2= a^2 + 2ab+b^2
(13x+a)^2= (13x)^2 +2 * 13xa+a^2= 169x^2+26ax+a^2
(11y)^2=(11y)^2 + 2 * 11y *3p + (3p)^2= 121y^2 + 66py + 9p^2
(9a + b)^2 = (9a)^2 + 2 * 9ab + b^2 = 81a^2 + 18ab + b^2
b. (5x-5)^2 = 25x^2 - 50x + 25
(12a-6x)^2 = 144a^2 - 144ax + 36x^2
(18p-18y)^2 = 324p^2 - 648py + 324y^2
(58x-45a)^2 = 3364x^2 - 5220ax + 2025a^2
(27y-18x)^2 = 729y^2 - 972xy + 324x^2