4c^2+12c+9

25x^2+10x+1

1+a^2-2a^2

4xy+y^2+4x^2

28ab+49a^2+4b^2

(x^2+3y) ^2

(o, 3a^2+4b) ^2

(0,2m^2-5n) ^2

4c^2+12c+9 = (2c+3) ²

25x^2+10x+1 = (5 х+1) ²

1+a^2-2a^2 = (1-а) ²

4xy+y^2+4x^2 = (у+2 х) ²

28ab+49a^2+4b^2 = (7 а+2b) ²

(x^2+3y) ^2=х ∧4+6 ху+9 у²

(o, 3a^2+4b) ^2=0,09 а ∧4+2,4 а∧2b+16b²

(0,2m^2-5n) ^2=0,04m ∧4-2mn+25n²