Trong không gian Oxyz, cho ba vectơ a=(x1;y1;z1), b=(x2;y2;z2), c=(x3;y3;z3)

A. $\left|\left(\overrightarrow{\mathrm{a}}.\overrightarrow{\mathrm{b}}\right)\overrightarrow{\mathrm{c}}\right|=\left|\left(\overrightarrow{\mathrm{c}}.\overrightarrow{\mathrm{b}}\right)\overrightarrow{\mathrm{a}}\right| \mathrm{với} \mathrm{mọi} \overrightarrow{\mathrm{a}},\overrightarrow{\mathrm{b}},\overrightarrow{\mathrm{c}}$

B. $\left(\overrightarrow{\mathrm{b}}+\overrightarrow{\mathrm{a}}\right)\overrightarrow{\mathrm{c}}=\overrightarrow{\mathrm{a}}.\overrightarrow{\mathrm{c}}+\overrightarrow{\mathrm{b}}.\overrightarrow{\mathrm{c}}$

C. $\left(\overrightarrow{\mathrm{b}}.\overrightarrow{\mathrm{c}}\right)\overrightarrow{\mathrm{a}}\ge 0$

D. ${\left(\overrightarrow{\mathrm{a}}+\overrightarrow{\mathrm{b}}+\overrightarrow{\mathrm{c}}\right)}^2<0$