Răspuns:
[tex]a)3a \times 6 \times ( - 2ab) = 18a \times ( - 2ab) = - 36 {a}^{2}b [/tex]
[tex]b) - 3 \times 2x \times ( - x) = - 6x \times ( - x) = 6 {x}^{2} [/tex]
[tex]c) \frac{1}{3} a \times \frac{2}{5} b \times ( - \frac{21}{4} a) = \frac{2}{15}ab \times ( - \frac{21}{4}a) = - \frac{42}{60} {a}^{2}b = - \frac{21}{30} {a}^{2}b [/tex]
[tex]d) - \frac{1}{2} {x}^{2}a \times ( - 6 {x}^{2} {a}^{2} ) = \frac{6 {x}^{4} {a}^{3} }{2} = 3 {x }^{4} {a}^{3} [/tex]
