Consider the following for the two (02) items that follow:
Let the function y = (1 - cos x)-1 where and n is an integer
What is the range of the function?
- AOption (a)
[0,∞)
- BOption (b)
[0.5,∞)
- COption (c)
[1,∞)
- DOption (d)
(−∞,0.5]
View answer & explanationHide answer & explanation
Correct answer
[0.5,∞)
Why this answer is correct
Calculation:
Given,
The function is, where and n is an integer.
The cosine function has a range of [-1, 1] , so cos(x) can take values from ( -1) to ( 1 ).
The expression will take values from:
So, (1 - cos(x)) takes values in the range , but excludes the value 0.
Since , the reciprocal function will take values in the range
∴ The range of the function is .
The correct answer is Option (b)