Question

Como é que faz essa conta ?

Answer 1

$x=( -\frac{1}{3})^3+[3^{-1}-(-3)^{-1}]^{-2}= -\frac{1}{27}+[ \frac{1}{3} -(-\frac{1}{3} )]^{-2}\\ \\x= -\frac{1}{27}+[\frac{1}{3} +\frac{1}{3}]^{-2}= -\frac{1}{27}+[\frac{1+1}{3}]^{-2}\\ \\x= -\frac{1}{27}+[\frac{2}{3}]^{-2}= -\frac{1}{27}+[\frac{3}{2}]^{2}\\ \\x= -\frac{1}{27}+\frac{9}{4}= -\frac{4}{108}+\frac{243}{108}=\frac{-4+243}{108}=\frac{239}{108}\\x=\frac{239}{108}$

$y= \frac{2^{-2}+2^2-2^{-1}}{2^{-2}-2^{-1}} = \frac{(\frac{1}{2})^{2}+2^2-\frac{1}{2}}{(\frac{1}{2})^2-\frac{1}{2}}\\ y= \frac{\frac{1}{4}+4-\frac{1}{2}}{\frac{1}{4}-\frac{1}{2}}= \frac{\frac{1}{4}+\frac{16}{4}-\frac{2}{4} }{\frac{1}{4} -\frac{2}{4}} =\frac{\frac{1+16-2}{4}}{\frac{1-2}{4}} =\frac{15/4}{-1/4}=\frac{15}{4} \cdot(-\frac{4}{1})=-\frac{60}{4} =-15\\y=-15$