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prottvip


1) |sinx| + |cosx|= 2sinx - sin^2x
2) cos5xcosx =1
3) cos2x - cos6x + 4sin3x + 4 = 0
4) sin^10x + có^6x = 1
5) Tìm các góc tg ABC biết :
a)sin^2A + cos^2B +1/2 = sinA + cosA
b)cos2A + cos2B - cos2C = 3/2
c)cosA +căn2(cosB + cosC) = 2
Mong mọi ng' giúp mình. Thanks ^^
2) cos5xcosx =1
3) cos2x - cos6x + 4sin3x + 4 = 0
4) sin^10x + có^6x = 1
5) Tìm các góc tg ABC biết :
a)sin^2A + cos^2B +1/2 = sinA + cosA
b)cos2A + cos2B - cos2C = 3/2
c)cosA +căn2(cosB + cosC) = 2
Mong mọi ng' giúp mình. Thanks ^^