lga(b)=c ⇒ b = a^c ; loga(b)=logc(a)/logc(b)1) 2x+1=10^3=1000 x = 499,52) 4+6x= 10^(-1)=0,1 x= - 0,653) log5(5)/log5(1/5)=1/(-1)=x x= -14) = 6 ·3·log6 =18·log6 = log (6^18) (нет основание log)5) = 2^(3log2(a)) = 2^log2(a³) = a³6 logx = log(3·5/2) x =7,57) (x+4)/(x-3) = 8 ⇒ x+4=8x-24 x = 48) lg[(3x-11)·(x-27)]=3 3x² -81x-11x+297 = 10³ 3x² - 92x -703 =0 x = [92 +/-√(92²+4·3·703)] /(2·3) x = (92 +/-130)/6 x1 = 37 x2 = - 38/6 не уд., так как 3x- 11<0 x = 37 9) log2{(x-5)·(x+2)] = 3 ⇒ x² -3x - 10 = 2³ x² - 3x - 18 = 0 x1= 6 x2 = -3 не уд, т.к. x-3 = -6<0 x= 6