How to find the values of k?

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Can someone please explain to me how to do question 5a? Thanks!

1 Answer
Jan 24, 2018

k=1/ln(9)

Explanation:

The trick to answering this question is to remember that the area under the probability density function for all allowed values of the variable must be 1. Therefore:

int_1^9 k/x dx = 1

k [ln(x)]_1^9 = 1

k*[ln(9)-ln(1)] = 1

k=1/ln(9)