# Math Help - Differentiating functions with integrals in them...?

1. ## Differentiating functions with integrals in them...?

$f(x,t)=\int_{0}^{t}\frac{1}{1-s}dx$

s is a dummy for t
x is a function of t

how can I find the partial derivatives? I think $f_{x}(x,t)=\frac{1}{1-t}$ - is this right?

But I have no idea how to find $f_{t}(x,t)$

Thanks for any help

2. In the expression...

$\int_{0}^{t} \frac{dx}{1-s}$ (1)

... x is the integration variable, so that the (1) i function of t and s, not of x that 'disappears' in computing integral...

Kind regards

$\chi$ $\sigma$