a) 3 cot2x = 1
cot2x = 1/3
cot x = √3 /3
x = π/3 , 2π /3
*2π /3≈ 2.094 is extraneous because it's out of the interval:
∴x = π/3
b) sin x= tan x
sin x- tan x = 0
sin x - sin x/ cos x = 0
(cos x• sin x - sin x)/ cos x = 0
[sin x(cos x - 1)] / cos x = 0
tan x (cos x - 1) = 0
tan x = 0 or cos x -1 = 0
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tan x = 0
x = 0
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cos x - 1 =0
cos x = 1
x = 0