PTLG TRONG CAC DE THI ĐH 2002-2010

PHƯƠNG TRÌNH LƯƠNG GIÁC TRONG CÁC ĐỀ THI ĐẠI HỌC 1. (1 + sin 2 x)cosx + (1 + cos 2 x)sinx = 1 + sin2x 2. 2sin 2 2x + sin7x – 1 = sinx 3. x x 2 (sin cos ) 3 cos x 2 2 2 + + = 4. 1 1 sin 2x sin x 2cot 2x 2sin x sin 2x + − − = 5. 2 2cos x+2 3sinxcosx+1=3(sinx+ 3cosx) 6. 5x x 3x sin( ) cos( ) 2 cos 2 4 2 4 2 π π − − − = 7. sin 2x cos2x tan x cot x cos x sin x + = − 8. 2 2 sin(x )cos x 1 12 π − = 9. (1 – tanx)(1 + sin2x) = 1+ tanx 10. 1 1 7 4sin( x) 3 sin x 4 sin(x ) 2 π + = − π − 11. 3 3 2 2 sin x 3 cos x sin x cos x 3sin x cos x− = − 12. 2sinx(1 + cos2x) + sin2x = 1 + 2cosx 13. tanx = cotx + 4cos 2 2x 14. 2 sin(2x ) sin(x ) 4 4 2 π π − = − + 15. 1 2sin(x ) sin(2x ) 3 6 2 π π + − − = 16. 3sinx + cos2x+sin2x=4sinxcos 2 x 2 17. 4(sin 4 x + cos 4 x) + cos4x + sin2x = 0 18. (1 2sin x)cos x 3 (1 2sin x)(1 sin x) − = + − 19. 3 cos5x – 2sin3xcos2x – sinx = 0 20. sinx + cosxsin2x + 3 cos3x = 2(cos4x + sin 3 x) 21. (1 sinx cos2x)sin(x ) 1 4 cos x 1 t anx 2 π + + + = + 22. (sin2x + cos2x)cosx + 2 cos2x – sinx = 0 23. sin2x – cos2x + 3sinx – cosx – 1 = 0 24. 3 3 2 3 2 cos3x cos x sin 3x sin x 8 + − = 25. 2sin(2x – 6 π ) + 4sinx + 1 = 0 26. cos2x + (1 + 2cosx)(sinx – cosx) = 0 27. (2sin 2 x – 1)tan 2 2x + 3(2cos 2 x – 1) = 0 28. 4sin 3 x + 4sin 2 x + 3sin2x + 6cosx = 0. 29. cos 3 x + sin 3 x + 2sin 2 x = - 1 30. 6 6 2(cos x sin x) sin x cos x 0 2 2sin x + − = − 31. x cot x sinx(1 tan x tan ) 4 2 + + = 32. cos3x + cos2x – cosx - 1 =0 Bài tập thêm 1. 2 17 sin(2 ) 16 2 3.sin cos 20sin ( ) 2 2 12 + + = + + x x x x π π 2. 2 sin 4 (1 sin 2 ) 1 tan cos   −  ÷   + = + π x x x x 3. 1 1 sin 2 sin 2cot 2 2sin sin 2 + − − =x x x x x 4.sin .tan 2 3(sin 3 tan 2 ) 3 3+ − =x x x x 5. cos2 5 2(2 cos )(sin cos )+ = − −x x x x voxuantruong.ht 6. 3 3 sin .(1 cot ) cos (1 tan ) 2sin 2+ + + =x x x x x 7. 3 3 sin .sin 3 cos cos3 1 8 tan tan 6 3 + = −     − +  ÷  ÷     π π x x x x x x 8. 2 2 1 sin sin cos sin 2cos 2 2 4 2   + − = −  ÷   x x x x x π 9. 3 3 2 cos cos3 sin sin 3 4 + = x x x x 10. 2 2 3 3 tan tan .sin cos 1 0− + − =x x x 11. 2 2 1 8 1 2cos cos ( ) sin 2 3cos( ) sin 3 3 2 3 + + = + + + + π π x x x x x 12.9sinx + 6cosx – 3sin2x + cos2x = 8 13.       π π π − − − = +  ÷  ÷  ÷       2 3 cos x- 4 2 x 4sin 3 sin 2x 1 2 2 2 14. − = − 2 2 2 2 sin 3x cos 4x sin 5x cos 6x 15.     + + − + =  ÷  ÷     π π x x x x 3 2 2 cos 2 sin 2 cos 4sin 0 4 4 16.9sinx + 6cosx – 3sin2x + cos2x = 8 17. 6 6 2 2 sin cos 1 tan 2 cos sin 4 + = − x x x x x 18.tan( 5 2 π -x) + sinx 1 + cosx = 2 19.2cos3x + 3 sinx + cosx = 0 20.cos 2 3xcos2x – cos 2 x = 0. 21. sin 2 2 2(sinx+cosx)=5 − x voxuantruong.ht . PHƯƠNG TRÌNH LƯƠNG GIÁC TRONG CÁC ĐỀ THI ĐẠI HỌC 1. (1 + sin 2 x)cosx + (1 + cos 2 x)sinx = 1 + sin2x 2. 2sin