Let's solve this
We need to accept solutions in the given interval 0 ≤ x < 2 pi
tanx * sinx - tanx = 0 First we pull out tanx in front of the bracket and get
=> tanx ( sinx - 1 ) = 0 now we interpret product and get
tanx = 0 or sinx - 1 = 0
When tanx = 0 => angle is x1=0
sinx - 1 = 0 => sinx = 1 When sinx = 1 then angle is x2= pi/2
The solutions are inside given interval 0 ≤ x < 2 pi and we accept it.
The correct answer is (x1, x2) = (0, pi/2)
Good luck!!!