The least value of 2sin^2theta+3cos^2the...

The least value of `2sin^2theta+3cos^2theta` is 1 (b) 2 (c) 3 (d) 5

A

1

B

2

C

3

D

5

Text Solution

Verified by Experts

The correct Answer is:

B

`sin^4theta+cos^4theta=2(sin^2theta+cos^2theta)+cos^2theta`
`=2+cos^2thetagt2 [:'cos^2thetagt0]`

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