Science:Math Exam Resources/Courses/MATH100/December 2018/Question 05 (a)
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Question 05 (a) 

Let (a) Find on which intervals is increasing and on which intervals is decreasing. 
Make sure you understand the problem fully: What is the question asking you to do? Are there specific conditions or constraints that you should take note of? How will you know if your answer is correct from your work only? Can you rephrase the question in your own words in a way that makes sense to you? 
If you are stuck, check the hint below. Consider it for a while. Does it give you a new idea on how to approach the problem? If so, try it! 
Hint 

When is increasing, what can you say about ? Similarly, what can you say about when is decreasing? 
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Solution 

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Please rate my easiness! It's quick and helps everyone guide their studies. We take the derivative . The function therefore has two critical points: at . Now using a chart of signs shows that exactly when . We conclude that . 