[tex]-15=- \frac{15}{1} \\
\\0,(12)= \frac{12}{99} \\\\
- \frac{15}{1} *(- \frac{23}{4}) * \frac{12}{99} :(- \frac{21}{2} )\\\\
+ \frac{345}{4} * \frac{12}{99}:(- \frac{21}{2} )\\\\
+ \frac{1035}{99} * \frac{2}{21} \\\\
=+ \frac{690}{693} \\
=+0,995[/tex]
Explicatie:Transformam toate nr.in fractii.Fractia (-15)=15/1
Fractia 0,(12) se transforma punandu-se atatea cifre de 9 cate sunt in perioada si atatea de 0 cate sunt intre perioada si intreg,neavand nr intre zecimale si 0 nu se pune niciun 0.
