Задача

[Гост]

IMG_20231105_115646.jpg (41.94 KiB) Прегледано 468 пъти

[ammornil]

(а) [tex]A=(x+m)^{3}-x(x-m)(x+m)-m^{3}=x^{3}+3mx^{2}+3m^{2}x\cancel{+m^{3}}-x(x^{2}-m^{2})\cancel{-m^{3}}=\\ \hspace{1em} = \cancel{x^{3}}+3mx^{2}\red{+3m^{2}x}\cancel{-x^{3}}\red{+m^{2}x}=3mx^{2}+4m^{2}x[/tex]
(б) [tex]3m=9 \Rightarrow m=3[/tex]