how to solve logarithm equation
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i want to solve an logarithm equation and find the value of x
log10(x^4)-log10(x^3) == log10(5*x) -log10(2*x)
4 commentaires
Davide Masiello
le 11 Oct 2022
Modifié(e) : Davide Masiello
le 11 Oct 2022
I believe that reduces to
and therefore there's no real solution to it
log10(4/3) == log10(5/2)
MANANJAYA NAYAK
le 11 Oct 2022
Ghazwan
le 11 Oct 2022
syms a b c x
eqn = a*x^2 + b*x + c == 0
S = solve(eqn)
David Hill
le 11 Oct 2022
Use fzero to solve a non-linear equation numerically. fzero
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Plus de réponses (2)
if you plot, it never crosses zero.
f=@(x)log10(4*x)-log10(3*x) -log10(5*x) +log10(2*x)
fzero(f,1)
log10(4*x)-log10(3*x) = log10((4*x)/(3*x)) = log10(4/3)
log10(5*x)-log10(2*x) = log10((5*x)/(2*x)) = log10(5/2)
So you try to "solve"
log10(4/3) = log10(5/2)
You can imagine that this makes no sense.
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