The least value of 3sin2θ+4cos2θis
2
3
0
1
Solve the given expression
Given expression, 3sin2θ+4cos2θ
=3(1-cos2θ)+4cos2θ …[∵sin2θ+cos2θ=1]
=3-3cos2θ+4cos2θ
=3+cos2θ Now, the So, the minimum value will be obtained ,when the value ofcos2θ=0
Therefore ,the least value of 3sin2θ+cos2θ=3