Bai 1:Giai các phương trình lượng giác sau
id
1) sin 27 + 22 cos x + 2sin(x + 7? +3=0
sln — cos — + sin — cos — + SIII 2T COS f#† =
3)
cos” (x +) +cos (2x +.) +cos” (3x =2) = v3 cos =
4X 4K
COS ——SIn —
4)
sin 2x 2sin? (x + 7)
5) cos Tx + sin Sx = cos $x — sin 2x
6) 2sinz + cos x = sin 2x + |
sin“ (— — —).tg°x — cos” — = O
sin xz cos 4x — sin* 27 = 4sin*(— — =)—- =
tq 3) 2
cos? x(cos x — 1)
——————-= 2(1+sinz)
9) sinx + cosx
10) 9sin # + 6cos # — 3sIn 2# + cos 2 = 8
tg2a —tgx = 3 cos © sin 3x
11)
sin’ z+ cos’ a tg?
ron SB COT Ger — ~—_
12) = Ssin 2x 2 8 sin 2x
2cos 3+ — Ÿcos ấø + Ï =
‘ » Of * ¢
(2 — sin* 227) sin3x
cos 2z " ; cot gx — 1 = —— + sin’ xr — ~sindr
16) 3 — tgx(tgx + 2sinx) + 6cosx = 0
2 cot gx — tgx + 4sin 2x2 = ——
sin 27
17)
9
18) €0S 2+ + cos (2£g + — 1) = 2
tgx + cosr — cos? x = sin z.(l+ tgx.tg>)
24 3/2
19)
cos 32 cos” © — Sin3xsin’s =
20) +
21) 3 + cofx= 3= +)
sin x cos x
2sin2x+2cosx—2sinx—-1
2cosx—-l
sin? x + cos*z = — (1+ sin2:) (cos x — sin)
Bai 1:Giai các phương trình lượng giác sau
TT 1) sin 2z + 2V2 cos z + 2sin(z + 1) +3=0
<=> sin2r + 24/2 cos rt V3 (szmø + cosz) + 3 = U
<=> V2.sinz(V2.cosz +1)+ 3.(V/2.cosxr +1)=0 3)
Sữn“m + stn “2+ + sin “3+ — 5
<=> cos?r+ cos4r+ cos6r = 0
537 sin — cos > + sin = cos > +sin2rcos 7x = 0
2 stnort+ sindrt+singr— sin2rt sindr—sinos = 0 <=> sindr+sindr = 0