[tex] \frac{7}{3* 2^{98} } = \frac{3n-1}{2^{100}- 2^{98} } [/tex]
[tex] \frac{7}{3* 2^{97} } = \frac{3n-1}{ 2^{98}( 2^{2} -1) } [/tex]
[tex] \frac{7}{3* 2^{97} }= \frac{3n-1}{ 2^{98} *3} [/tex]
Aducem la acelasi numitor si eliminam numitorii. Num comun este:[tex]3* 2^{98} [/tex] prima fractie o amplificam cu 2
7*2=3n-1
14=3n-1
3n=14+1
3n=15
n=15/3
n=5