Given: 1+sin2θ=3sinθcosθ
sin2θ+cos2θ=1
sin2θ=1−cos2θ
1+(1−cos2θ)=3sinθcosθ
2−cos2θ=3sinθcosθ
cos2θ2−cos2θ=cos2θ3sinθcosθ
cos2θ2−1=3⋅cosθsinθ
cos2θ1=1+tan2θ and cosθsinθ=tanθ
2(1+tan2θ)−1=3tanθ
2+2tan2θ−1=3tanθ
1+2tan2θ=3tanθ
2tan2θ−3tanθ+1=0
t=tanθ
2t2−3t+1=0
t=43±9−8
t=43±1
t=44=1 or t=42=21
Therefore, tanθ can take the values 21 and 1.