(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

So I understand how to evaluate P(4 < X < 6) where the probability density function is f(x)=4x

I cant seem to understand how to evaluate P(X>6)

I would have to do something like [tex]\int^6_\infty 4x [/tex] ... so how do I evaluate it?

2. Relevant equations

3. The attempt at a solution

The answer from my book suggests this, after integration = > 2x^{2}Then

2([tex]\infty[/tex])^{2}- 2(6)^{2}

my 2([tex]\infty[/tex])^{2}should evaluate to 1.. however in some other problems when its [tex]\int^4_\infty 4x [/tex] (infinity being -infinity) the - [tex]\infty[/tex] part should end up being zero? I'm sorry if this is something basic but there aren't enough examples in my book.

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# Evaluating infinite integral for probability density functions

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