Question

Раскройте скобки (z+x+3) во 2 степени

Answer 1

$(z + x + 3)^{2} = {z}^{2} + {x}^{2} + 9 + 2xz + 6x + 6z$

Answer 2

$\displaystyle \tt (z+x+3)^2=z^2+x^2+3^2+2zx+2z\cdot3+2x\cdot3=z^2+x^2+9+2xz+6z+6x$