Calcula e simplifica
Equações de grau superior ao 1.º: Matematicamente Falando 8 - Parte 2 Pág. 66 Ex. 13
Enunciado
Calcula e simplifica:
- $3\times 5x$
- $2a\times (-a)$
- $-3yz\times \frac{1}{3}y$
- $-2{{x}^{2}}\times (-5{{x}^{3}})$
- $3{{a}^{2}}b\times \frac{ab}{3}$
- ${{({{x}^{2}}y)}^{2}}$
- ${{\left( -\frac{1}{2}m{{n}^{2}}p \right)}^{3}}$
Resolução
- $3\times 5x=(3\times 5)\times x=15x$
- $2a\times (-a)=2\times (a\times (-a))=2\times (-{{a}^{2}})=-2{{a}^{2}}$
- $-3yz\times \frac{1}{3}y=(-3\times \frac{1}{3})\times (yz\times y)=-1\times {{y}^{2}}z=-{{y}^{2}}z$
- $-2{{x}^{2}}\times (-5{{x}^{3}})=(-2\times (-5))\times ({{x}^{2}}\times {{x}^{3}})=10\times {{x}^{5}}=10{{x}^{5}}$
- $3{{a}^{2}}b\times \frac{ab}{3}=(3\times \frac{1}{3})\times ({{a}^{2}}b\times ab)=1\times {{a}^{3}}{{b}^{2}}={{a}^{3}}{{b}^{2}}$
- ${{({{x}^{2}}y)}^{2}}={{x}^{2}}y\times {{x}^{2}}y={{x}^{4}}{{y}^{2}}$
- ${{\left( -\frac{1}{2}m{{n}^{2}}p \right)}^{3}}=(-\frac{1}{2}m{{n}^{2}}p)\times (-\frac{1}{2}m{{n}^{2}}p)\times (-\frac{1}{2}m{{n}^{2}}p)=-\frac{1}{8}{{m}^{3}}{{n}^{6}}{{p}^{3}}$
