Question

How do you do this question?

Answer 1

p > 0

Explanation:

∫₂°° e^(-px) dx

= ∫₂°° (e⁻ᵖ)ˣ dx

This is a geometric series.

A geometric series a(r)ˣ converges if -1 < r < 1.

-1 < e⁻ᵖ < 1

Since e⁻ᵖ is always positive:

e⁻ᵖ < 1

-p < 0

p > 0