Question
if 7 sin 2 x + 2 cos 2 x = 4
then find tan xSolution
7 sin 2 x + 2 cos 2 x = 4 ----- (1) Now we know that sin2 x + cos2 x = 1 or 7 sin2 x + 7 cos2 x = 7 ----(2), So by solving equation (1) & (2), we will get, cos2 x = 
or cosx = Putting the value of cosx in equation (1), we will get sin x = so tan x = = = = =
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