Log_1/3 (7x-4x^2)=-1
㏒₁₎₃ (7х-4х²)= -1 7х-4х²=(1/3)⁻¹ 7х-4х²=3 4х²-7х+3=0 D=49-48=1 х₁=(7+1)/8=1 х₂=(7-1)/8=6/8=3/4