Find the minimum value of `2sin^2theta+3cos^2theta`

1.	Find the minimum value of `2sin^2theta+3cos^2theta`
Answer» `f(theta) = 2sin^2theta+3cos^2theta` `= 2(cos^2theta+sin^2theta)+cos^2theta` `=2+cos^2theta` `=2+1/2(1+cos2theta)` `=2+1/2+1/2cos2theta` `f(theta)=5/2+1/2cos2theta` `f(theta)` will be minimum when `cos2theta = -1` `:f(theta)_min = 5/2-1/2 = 2 `

Discussion

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