[R] R solve equation

rafamoral rafa_moral2004 at yahoo.com.br
Sun Feb 8 23:05:11 CET 2009

If you are looking for a solution to a polynomial equation with imaginary
solutions you could use polyroot().
To solve the equation: 1 + x + x^3 + 2*x^4 = 0
you create a vector with the coefficients of x and use polyroot:

z <- matrix(c(1,1,0,1,2), ncol=1)

Also try ?polyroot


Paul Smith wrote:
> On Sat, Feb 7, 2009 at 10:20 AM, oryie <43248523 at qq.com> wrote:
>> I want to use R to calculate the variable x which is in some eqation,
>> give
>> an example:
>> 3*x-log(x)+1=0,
>> how to solve equation to get the exact x in R?
> You could use uniroot(), but your equation has no real solution.
> Paul
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