Giải phương trình:
3sin2x + 2cos2x = 3
a) cos2x - sinx + cosx = 0
b) 2cos³x + sinx + cos2 = 0
1. Cosx.cos7x = cos3x.cos5x
2. Sin3x - 4sinx.cos2x = 0
3. Sinx + 3sin2x + sin3x = 0
4. Sinbình2x - cosbình2x + 3/4 = 0
5. Sinbìnhx + sinbình2x = 1
cos2x-3sinx=0
cos2x + cosx + 1 = 0
cos2x-sinx+2=0
cosx + cos2x + cos3x = 0
cosx + cos2x + cos3x + 1 = 0
giải các pt sau:
a) cosx(1-cos2x) - sin^2x = 0
b) sin3x + cos2x = 1 + 2sinxcos3x
c) ( cosx+1)(sinx - cosx + 3) = sin^2x
d) (1+sinx)(cosx-sinx) = cos^2x
1.Sin²2x-cos2x+1=0
2.sin²x/4-3cosx/4=0
3.tan7x-3cot7x+2=0