Leading Order $\epsilon \frac{\mathrm{d}^2y }{\mathrm{d} x^2} + 12x^{\frac{1}{3} }\frac{\mathrm{d} y}{\mathrm{d} x}+y= 0 $

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I am required to find the leading order outer and inner solutions and then the constants by asymptotic matching.

I have shown there exists a boundary layer at x=0 and hence have use the condition$ y(1)=1$ to find the leader order outer solution to be $y_0(x)$ ~ $e^{\frac{1-x^{\frac{2}{3}}}{8}}$. I then rescaled writing $x= \epsilon^{\frac{3}{4}}X$ and found the leading order inner solution to be $Y_0(X)$ ~ $A + c \int_{0}^{X}{e^{-9s^{\frac{4}{3}}}} ds$. I then used the boundary condition $y(0)=1$ to find A=1 by taking the limit as X tends to infinity. Is this right?

My main issue is how to find $c$ using asymptotic matching. In previous examples I have seen, it has been easy to approximate the integral in the inner solution and hence match with the outer solution. Any help would be greatly appreciated.

Thanks