Question

Efetue e Simplifique
a) 1/4y² (10-y)
b) - 1/2 (2a-8)
c) -5m (- 1,2 - 4/5m)
d) x/6 (x/2 - 6x² + 12)

Answer 1

$a)\\ \\ \frac{1}{4y^{2}} (10-y)=\frac{10-y}{4y^{2}} =\frac{10}{4y^{2}} -\frac{y}{4y^{2}} =\frac{5}{2y^{2}} -\frac{1}{4y} \\ \\ mmc=4y^{2} \\ \\ \frac{10-4y}{4y^{2}} \\ \\ b)\\ \\-\frac{1}{2} (2a-8)=\frac{-2a+8}{2} =-\frac{2a}{2} +\frac{8}{2} =-a+4~ou~4-a$

$c)\\ \\ -5m(-1,2-\frac{4}{5m} )\\ \\ 1,2=\frac{12}{10}=\frac{6}{5} \\ \\ -5m(-\frac{6}{5} -\frac{4}{5m} )=\frac{30m}{5} -\frac{20m}{5m} =\\ \\ 6m-4\\ \\ d)\\ \\ \frac{x}{6} (\frac{x}{2} -6x^{2} +12)\\ \\ mmc=2\\ \\ \frac{x}{6} (\frac{x-12x^{2}+24}{2} )=\frac{x^{2}-12x^{3}+24x}{12} =\frac{x^{2}}{12} -\frac{12x^{3}}{12} +\frac{24x}{12} =\\ \\ \frac{x^{2}}{12} -x^{3} +12x$