# Science:Math Exam Resources/Courses/MATH103/April 2012/Question 05 (a)

MATH103 April 2012
Other MATH103 Exams

### Question 05 (a)

A professor never finishes his class on time. The time of delay is given by the probability density function

{\displaystyle {\begin{aligned}p(t)={\frac {k}{1+t^{2}}},{\text{ where }}0

You can use the facts that ${\displaystyle \displaystyle \arctan(0)=0}$ and ${\displaystyle \arctan({\sqrt {3}})=\pi /3}$.

(a) What is the constant k?

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