How do you find all solutions in [0, 2π): 3tan^2x - 1 = 03tan2x1=0?

1 Answer
Oct 11, 2016

Solution: In [0,2pi) x=pi/6,x=(7pi)/6 and x=(5pi)/6, x= (11pi)/6[0,2π)x=π6,x=7π6andx=5π6,x=11π6

Explanation:

3tan^2x-1=0 or3tan^2x=1 or tan^2x=1/3 or tanx=+- 1/sqrt33tan2x1=0or3tan2x=1ortan2x=13ortanx=±13. We know tan(pi/6)= 1/sqrt3 and tan(pi+pi/6)= 1/sqrt3 tan(π6)=13andtan(π+π6)=13 and also
tan(2pi-pi/6)= -1/sqrt3 and tan(pi-pi/6)= -1/sqrt3 tan(2ππ6)=13andtan(ππ6)=13.
Solution: In [0,2pi) x=pi/6,x=(7pi)/6 and x=(5pi)/6, x= (11pi)/6[0,2π)x=π6,x=7π6andx=5π6,x=11π6[Ans]