Log20 120 = log20 (20 * 6) =
=log20 20 + log20 6 =
=1 + (1 / 2) * log20 (6 ^ 2) =
=1 + (1 / 2) * log20 36 =
=1 + (1 / 2) * (log20 9 + log20 4)=
=1 + (1 / 2) * (1 / (log9 20) + 2 * log20 2)
=1 + 1 / (2a) + log20 2=
=1 + 1 / (2a) + 1/(log2 20)=
=1 + 1 / (2a) + 1/(log2 10 + log2 2)=
=1 + 1 / (2a) + 1/(1/(lg 2) + 1)=
=1 + 1 / (2a) + 1 / (1 / b + 1)
7c/(c+2) -(c-8)/3(c+2) * 84/c(c-8)=7c/(c+2) - 28/c(c+2)=(7c²-28)/c(c+2)=
=7(c-2)(c+2)/c(c+2)=7(c-2)/c=(7c-14)/c
-2x² + 5x + 7. Старший коэффициент: -2
3x² + x - 6. Свободный член: -6