0\\\\y'=3x-39+\frac{108}{x}= \frac{3x^2-39x+108}{x} =0\; ,\; x\ne 0\\\\3x^2-39x+108=0\\\\D=39^2-4\cdot 3\cdot 108=225\\\\x_1= \frac{39-15}{6}=4\; ,\; \; x_2= \frac{39+15}{6}=9\\\\Znaki\; y':\; \; \; +++(4)---(9)+++\\\\.\qquad \qquad \qquad \nearrow \; \; (4)\; \; \; \searrow \; \; (9)\; \; \; \nearrow \\\\x_{max}=4\\\\(\; x_{min}=9\; )" alt="y=1,5x^2-39x+108\cdot lnx+8\\\\ODZ:x>0\\\\y'=3x-39+\frac{108}{x}= \frac{3x^2-39x+108}{x} =0\; ,\; x\ne 0\\\\3x^2-39x+108=0\\\\D=39^2-4\cdot 3\cdot 108=225\\\\x_1= \frac{39-15}{6}=4\; ,\; \; x_2= \frac{39+15}{6}=9\\\\Znaki\; y':\; \; \; +++(4)---(9)+++\\\\.\qquad \qquad \qquad \nearrow \; \; (4)\; \; \; \searrow \; \; (9)\; \; \; \nearrow \\\\x_{max}=4\\\\(\; x_{min}=9\; )" align="absmiddle" class="latex-formula">