[tex]\frac{1}{C_{1,3}}}=\frac{1}{C_1}+\frac{1}{C_2}+\frac{1}{C_3}<=>\frac{1}{1,5}=\frac{1}{3}+\frac{1}{6} +\frac{1}{C_3}<=> 0,66= 0,33+ 0,166++\frac{1}{C_3}<=>0,166=\frac{1}{C_3}<=>C_3=\frac{1}{0,166}= 6\mu F=>C_3=6\mu F[/tex]
