First slide
Functions (XII)
Question

The period of the function f(x)=[8x+7]+tan2πx+cot2πx8x (where [.] denotes the greatest integer function), is _______.

Moderate
Solution

f(x)=[8x+7]+|tan2πx+cot2πx|8x=[8x]8x7+|tan2πx+cot2πx|={8x}+|tan2πx+cot2πx|+7

Period is {8x} is 1/8

Also, |tan2πx+cot2πx|=sin2πxcos2πx+cos2πxsin2πx

=1sin2πxcos2πx=|2cosec4πx|

Now, period of 2 cosec 4πx is 1/2. Then period of |2cosec4πx| is 1/4.

Therefore, period is L.C.M. of 18 and 14 which is 14

Get Instant Solutions
When in doubt download our app. Now available Google Play Store- Doubts App
Download Now
Doubts App