Y`=3x-45+150/x=(3x²-45x+150)/x=3(x²-15x+50)/x=0 x²-15x+50=0 x1+x2=15 U x1*x2=50⇒x1=5 U x2=10 + _ + __________________________________ 5 10 max min ymax=37,5-225+150ln5+8=150ln5-179,5 (5;150ln5-179,5)