Evil combination: Chem and Calc & Finding a Function

Hi there,

Two questions that have done my head in for the past couple of days; mind taking a look?

Question one

For the function y = c(e^-at – e^-bt)

With a, b, c, > 0 and t ≥ 0, find

i) y (0)
ii)the limit of y as t approaches infinity
iii)the point at which y reaches a maximum

Question two

In water and in solution the product of the concentrations of hydronium ions, [H3O+] and of hydroxyl ions, [OH-] is very close to 10^-14 (in moles).

Let S = [H3O+] + [OH-]

Determine the value of [H3O+] which minimises S.

Quote:

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Originally Posted by Wildharmony

Hi there,

Question one

For the function y = c(e^-at – e^-bt)

With a, b, c, > 0 and t ≥ 0, find

i) y (0)
ii)the limit of y as t approaches infinity
iii)the point at which y reaches a maximum

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i)


ii)
If

iii)

Can you go from there?

I believe i can; thankyou kindly =)