First slide

Extreme values and Periodicity of Trigonometric functions

Question

If $f (x) = \sin x (\sin^{3} x + 3) + \cos x (\cos^{3} x + 4) + \frac{1}{2} \sin^{2} 2 x + 5$ then the sum of extreme values of $f (x)$ is

Moderate

A

9
B

10
C

11
D

12

Solution

$f (x) = {(\sin^{2} x + \cos^{2} x)}^{2} + 3 \sin x + 4 \cos x + 5$
$= 3 \sin x + 4 \cos x + 6 m i n a n d m a x i s 6 \pm \sqrt{9 + 16} ∴ s u m = 12$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App