# How can I go about solving this equation?

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Thread starter 5 years ago
#1
I've started my A2 Maths and FM this year. I have not gotten far into the modules, and I'm sure I would be able to solve this equation when I will get through them, but I have been confused to how I can about solving the following equation:

ex = -ln(x)

The log skills from AS are not helpful here very much as they dont allow me to get x onto one side of the equation in order for me to solve it. Anyone care to help me out? Apparently using some sort of numerical methods (perhaps from FP1?) can help, but I would also like to see an algebraic way of doing this.

Thanks
0
5 years ago
#2
I'm not sure whether you can solve it analytically. I think numerical methods are the way to go.
That's why numerical methods exist
0
5 years ago
#3
(Original post by RDKGames)
I've started my A2 Maths and FM this year. I have not gotten far into the modules, and I'm sure I would be able to solve this equation when I will get through them, but I have been confused to how I can about solving the following equation:

ex = -ln(x)

The log skills from AS are not helpful here very much as they dont allow me to get x onto one side of the equation in order for me to solve it. Anyone care to help me out? Apparently using some sort of numerical methods (perhaps from FP1?) can help, but I would also like to see an algebraic way of doing this.

Thanks
Numerical is the way.
0
5 years ago
#4
If you start by graphing the function e^x + lnx =0, then use Newton-Raphson with x1 being 0.25.
1
5 years ago
#5
I don't do FM but can you show a pic of the question please.
0
Thread starter 5 years ago
#6
Numerical methods would only approximate the root? Linear interpolation and newton raphson would never give the exact answer as far as im aware, can someone show me how this is done?
0
5 years ago
#7
Pic?
0
Thread starter 5 years ago
#8
(Original post by Vikingninja)
Pic?
0
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