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[Chinni18]

I have a very silly and basic doubt but it's really bugging me:
The distribution function for a random variable X is F(x) = [1-{e^(-2x)}] if x>or=o
                                                                               and o if x<0
To find the density function, f (x) we do d/dx F(x) = 2[e^(- 2x) if x> 0 and o if x<0
My doubt is how did the sign in the bold change from a weak to strict inequality for a density function?
Would appreciate any inputs

[anon_econ]

actually u can put the equality sign anywhere.

[Chinni18]

Acha  I was wondering if it's a general thing. Thanks Vasudha!