Chuyªn ®Ị IIICác Phương Pháp Giải Bất Phương Trình Mũ và Logarit.          > ⇔ > >log log a a x y x y nếu a   > ⇔ < < < log log a a x y x y nếu a                !"        #$!"  %&  %  '()            %(  ('*  ##+  $, - .  &(#&  #&   ##  /"  (.  ((  (#+  $, - .  &(#0,  ##  /'*  # #+    %#  .)  %  %'*  ##+  %'  0 Bài 1: 1) ( ) ( ) 114log16log 2 2 2 −≥− xx 2) ( ) ( ) 2l g 1 . 5 l g 5 1o x o x   − > − +   3) 12log 3 <− x 4) 1 1 32 log 3 < − − x x 6) 03loglog 3 3 2 ≥− x 7) ( ) [ ] 113loglog 2 2 1 −>+ x 8) ( ) 2385log 2 >+− xx x 9) 0 1 13 log 2 > + − x x x 10) ( ) ( ) 12log log 5,0 5,0 2 25 08,0 − − −       ≥ x x x x 11) ( ) 322 2 2 2 loglog ≤+ xx x 12) ( ) 3 3 1 3 1 11loglog 2 1 −+< xx 14) 2 4 1 log ≥       − x x 15) ( ) 12log log 1 1 3 35 12,0 − − −       ≥ x x x x  1 0 1 0 > ⇔ − − > > ⇔ − − > 1 21 2 & & 1 21 2 x y a a a a a x y x y a x y      log log log log : log log > > ⇔ > > ⇔ > > ⇔ > > > ⇔ > < < > ⇔ < > ⇔ < < x y x a a a b a x y a a Nếu a thì a a x y a b x b x y x y x b x a Nếu a thì a a x y x y x y 16) 22004log1 <+ x 17) ( ) ( ) 3 5log 35log 3 > − − x x a a 18) ( ) 0)12(log322.124 2 ≤−+− x xx 19) 2 1 2 24 log 2 ≥         − − x x x 20) ( ) 1log 1 132log 1 3 1 2 3 1 + > +− x xx 21) x x x x 2 2 1 2 2 3 2 2 1 4 2 log4 32 log9 8 loglog <       +         − 22) ( ) ( ) 04log286log 5 2 5 1 >−++− xxx 23) ( ) [ ] 05loglog 2 4 2 1 >− x 24) ( ) 165 2 2 <+− xx x log 25) 15 2 log 3 < − x x 26) ( ) 1 1 13log 3 ≥ − − x x 27) ( ) ( ) 3 2 1 2 1 21log1log 2 1 −+>− xx 28) ( ) 22log1log 2 2 2 −−<+ xx Bài 2: 1) ( ) 032log225log 25 2 >−++ + x x 2) 03183 2 1 log log 3 2 3 >+− x x 3) ( ) 022log1log 2 2 2 >−++− xxxx 4) 4 logloglog.log 2 2 323 x xxx +< 5) 2 5 2 2 2 1 2 2 1 loglog >+ xx x 6) ( ) 63 3 2 3 loglog ≤+ xx x 7) ( ) 3 4 1 5 log 4 1 log 3 2 x x + + + > 8) xx 22 loglog2 >− Bài 3: gii cc bt phương trnh sau: a) 2 16 4 111 2 1 2x x− ≤ − b) 2 0 5 15 2 2 16 0 & 3& 4 x   − ≤  ÷   c) 2 2 2 1 5 1& 1 2 & 1 2x x− > − + d) 4 3 4 2 & & x x − ≤ 52 1 3 1 3 4 3 2 3 & & 1 2 x x x + < − − 62 2 3 1 0 1 & x x x − > + 2 2 0 5 4 6 0 7 & x x x − + < 2 1 2 2 1 2 0 1 & & x x +   >   +   (2 1 3 3 1 2 1 & x x − + < '  (8(  (%  %'*  ##+  !, 2 2 3 x x > '2 2 2 7 3 11 2 x x x − − > %2 1 4 2 3 x x+ < + 92 2 3 7 3 1 6 2 30 x x x+ + − < 52 2 1 0 5 0 5 5 2 0 08 2 & 1 2 1 7 2 1 7 2 & 1 7 2 x x x x − − −   ≥  ÷   : . Chuyªn ®Ị III Các Phương Pháp Giải Bất Phương Trình Mũ và Logarit.          > ⇔