#Algebra/Calculus Question

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safe mulch
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How to solve for x
x = 1.5 ln(x) + 2.5

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dense dune
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Plug it in geogebra. I don't think it can be solved analytically.

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Actually lets consider the function f(x)=1.5lnx+2.5-x, x>0 Find the intervals where the derivative preserves its sign you will find that for 0<x<1.5 f'(x)>0 → f strictly increasing and for x>1.5 f'(x)<0 f strictly decreasing. Find the value f(1.5) which is the global maximum of f.

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Now if f(1.5)<0 then that would mean your equation has no solutions.

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Unfortunately that is not the case and f(1.5)>0

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There could be up to two solutions one before x=1.5 and one after x=1.5

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Now you could apply some numerical method to solve this equation. Like Newton's method, or bisection method. Google those.

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Bisection method might work better because you know the intervals where the two solutions might lie.

safe mulch
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Thank you

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