Question

The least value of $3{\sin }^2\theta +4{\cos }^2\theta$ is

• A. $2$
• B. $1$
• C. $4$
• D. $3$

Answer 1

The correct option is D $3$

$3{\sin }^2\theta +4{\cos }^2\theta =3({\sin }^2\theta +{\cos }^2\theta )+{\cos }^2\theta =3+{\cos }^2\theta \ge 3$