# Science:Math Exam Resources/Courses/MATH100/December 2019/Question 5

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Critical points and intervals of increase and decrease

MATH100 December 2019

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Other MATH100 Exams

### Question 5

A ${\displaystyle 2}$ metre tall woman (yes, she’s tall!) is running away from a ${\displaystyle 6}$ metre tall lamp-post (with a light on top – it’s dark out). Her velocity t seconds after leaving the lamp-post is given by the equation ${\displaystyle v(t)=4-\sin(2\pi t)}$ metres per second. How quickly is the length of her shadow changing after ${\displaystyle 3}$ seconds?

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