Deriving the magnitude of error of absorance (true and measured) from Transmittance equation

Hi there,

I have just been going through some pastpapers and I came across the
following question:

we are given the following equation:

int(n10-A(L)dL)
T = --------------------
int(ndL)

Where T is the measured trasnmittance, n is a constant (originally
I(L)D(L)S(L) and L=wavelength = lamda.

A = log 1/T

We are then asked to derive the magnitude of error of absorbance
equation (diff b/w true and measure absorbance):

sinh(ln(10) delta A / 2)
_A_ - A = log ---------------------------------
ln(10) delta A/2

I have been trying all evening on this and still can't get anywhere. We
were also given the following equation:

A(L) = (delta A/ delta L) (L + (L1 + L2)/2) + _A_

Any help will be greatly appreciated.
Thanx

WB

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