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<span class='text_page_counter'>(1)</span>IV. MŨ, LOGARIT.

<span class='text_page_counter'>(2)</span> Bài 1:. 3 2  log 2  x  1 log 3  x  1. 1 log Bài 2: 2. 2.  x  3 . 1 8 log 4  x  1  3log 8  4x  4. log 3  2 x  1 .log 1  2 x 1  2   2 log 32 2  0.. Bài 3:. 3. x. Bài 4:.  20  14 2    20  14 2 . x.  43 x. x  3 log32  x  2   4  x  2  log 3  x  2   16  Bài 5:. Bài 6:.  2x2 y 1 2x  y 1 2log3x1  2x 1 1  log3x1 6x2  5x 1  2y4  22x1 1  0 .

<span class='text_page_counter'>(3)</span> Bài 7:. Bài 8:. 2 log 92 x  log 3 x.log 3. . . 2x  1  1. log 21 (5  2 x)  log 2 (5  2 x ).log 2 x 1 (5  2 x)  log 2 (2 x  5) 2  log 2 (2 x  1).log 2 (5  2 x) 2. x B2002 log x (log 3 (9  72))  1 (x  ). x D2003 2. x D2006 2. D2007. 2. 2. x. x.  4.2 x. 2. x.  22 x  4  0.  1  log 2 (4x  15.2 x  27)  2 log 2    0 (x  ) x  4.2  3 . log 1. D2008. 2.  2 2 x  x  3. 2. x 2  3x  2  0 (x  ) x.

<span class='text_page_counter'>(4)</span> x x 2 B2006 log 5 (4  144)  4 log 2 5  1  log 5 (2  1) (x  ). . . log 2 x 2  y 2  1  log 2  xy    2 2 3x  xy  y  81 A2009. log 2  3 y 1  x  x x 2 B2010 4  2  3 y. 2x  D2010 4. x2. 3.  2 x  42 . x2.  x 2  4 x  y  2  0  2log 2  x  2   log D2010 VIIb .  2x. 2. 3.  4x  4. y0. log 2 (8  x 2 )  log 1 ( 1  x  1  x )  2  0. D2011. 2.

<span class='text_page_counter'>(5)</span> 2 2 A2008 log 2x 1 (2x  x  1)  log x 1 (2x  1)  4. x x CĐ2011 4  3.2. x 2 2x 3.  41. x 2 2x 3. 0.  x2  x  log 0,7 (log 6  )  0 (x  ) x4   B2008. x x x x A2006 3.8  4.12  18  2.27  0. 2log 3 (4x  3)  log 1 (2x  3)  2. A2007. 3. V. PHƯƠNG TRÌNH LƯỢNG GIÁC.

<span class='text_page_counter'>(6)</span> 2 2 Bài 1: cos x  3 sin 2 x  1  sin x. 3. 3. 2. Bài 2: cos x  4sin x  3cos x.sin x  sin x  0. 3 Bài 3: sin2x  2tan x  3 sin x.sin 2 x  sin 3 x  6 cos x. cot x  1 . Bài 4:. cos 2 x. 1 2  sin x  sin 2 x 1  tan x 2. Bài 5 sin 3x  cos3x  2cos x  0. 3 Bài 6 sin x  4 sin x  cos x  0. 2 2 Bài 7 tan x.sin x  2sin x  3(cos 2x  sin x cos x). Bài 8 cos 3 x  4 cos 2 x  3 cos x  4  0. Bài 9 (2 cos x  1)(2sin x  cos x)  sin 2 x  sin x Bài 10 cos x  cos 2 x  cos 3 x  cos 4 x  0. 2 2 2 2 Bài 11 sin x  sin 3x  cos 2 x  cos 4 x.

<span class='text_page_counter'>(7)</span> 3 3 3 Bài 12 sin x cos3x  cos x sin 3x  sin 4 x. 3 3 2 Bài 13 4sin x  3cos x  3sin x  sin x cos x  0. 2 Bài 14 (2sin x  1)(3cos 4 x  2sin x  4)  4cos x  3. 6 6 8 8 Bài 15 sin x  cos x  2(sin x  cos x). cos x . cos 2 x. cos 4 x. cos 8 x . Bài 16. 1 16.    8 co s3  x    co s 3 x 3   Bài 17. 2 Bài 18 (2 sin x  1)(2 sin 2 x  1)  3  4 cos x. Bài 19 cos 2 x  cos 8 x  cos 6 x  1. Bài 20 sin 4 x  4sin x  4cos x  cos 4 x  1. Bài 21 3sin x  2 cos x  2  3 tan x 3 Bài 22 2 cos x  cos 2 x  sin x  0. Bài 23 2(tan x  sin x)  3(cot x  cos x)  5  0.

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