Julien Martin wrote:
> Hello,
> I wish to solve a simple equation. I tried solve and desolve to no avail.
> Can anyone please help?
> Here is the equation:
> 275.0*%e^(-r)+275.0*%e^(-2*r)+275.0*%e^(-3*r)+275.0*%e^(-4*r)+5275.0*%e^(-5*r)=4750.0
> I am trying to determine the value of r.
> Julien.
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1. try ratsubst(y,exp(-r), your_equation).
You then see it is a polynomial of degree 5.
namely
0=211*y^5+11*y^4+11*y^3+11*y^2+11*y-190
Try a numerical root finder like allroots, since solve will not be able
to find exact roots.