Question

The maximum value of $3\cos \theta +4\sin \theta$ is

• A. $-5$
• B. $5$
• C. $25$
• D. None of these

Answer 1

The correct option is B $5$

The maximum value of $3\cos \theta +4\sin \theta$
$=\sqrt{3^2+4^2}$
$=\sqrt{25}=5$