a) 4x(2x-1)-(x-3)(x+3)=(8x-4)*x-(x-3)*(x+3)=8x^2-4x-(x-3)*(x+3)=8x^2-4x-(x^2-9)=8x^2-4x-x^2+9=7x^2-4x+9
б) (x+3)(x-11)+(x+6)^2=x^2-8x-33+(x+6)^2=x^2-8x-33+x^2+12x+36=2x^2-8x-33+12x+36=2x^2+4x-33+36=2x^2+4x+3
в) 7(a+b)^2-14ab=7*(a^2+2ab+b^2)-14ab=7a^2+14ab+7b^2-14ab=7a^2+7b^2
a) 4x(2x-1)-(x-3)(x+3)=(8x-4)*x-(x-3)*(x+3)=8x^2-4x-(x-3)*(x+3)=8x^2-4x-(x^2-9)=8x^2-4x-x^2+9=7x^2-4x+9
б) (x+3)(x-11)+(x+6)^2=x^2-8x-33+(x+6)^2=x^2-8x-33+x^2+12x+36=2x^2-8x-33+12x+36=2x^2+4x-33+36=2x^2+4x+3
в) 7(a+b)^2-14ab=7*(a^2+2ab+b^2)-14ab=7a^2+14ab+7b^2-14ab=7a^2+7b^2