Science:Math Exam Resources/Courses/MATH100/December 2016/Question 09 (b) (iii)
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Question 09 (b) (iii) 

Let . (iii) Find all intervals where is decreasing. 
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Hint 

A function is decreasing on an interval if on the interval. 
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Solution 

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Please rate my easiness! It's quick and helps everyone guide their studies. From the solution of part (ii), we have when but since and are again undefined on and at we have that is decreasing on . 