English Deutsch Français Italiano Español Português 繁體中文 Bahasa Indonesia Tiếng Việt ภาษาไทย
All categories

(Exponential and logarithmic equations)Solve for x Algebraically.

2007-04-16 13:19:30 · 3 answers · asked by Rahim C 1 in Science & Mathematics Mathematics

3 answers

#1: I'm going to assume you mean log (√x^3) - 17 = 1/2, so if that's not what you mean, this answer is wrong.

log (√x^3) - 17 = 1/2
log (x^(3/2)) = 35/2
3/2 log x = 35/2
log x = 35/3
x=10^(35/3)

#2: ln (1-x)+ln(3-x)=ln 8
ln ((1-x)(3-x))=ln 8
(1-x)(3-x)=8
x²-4x+3=8
x²-4x-5=0
(x-5)(x+1)=0

x=5 or x=-1, however x≠5 since that would mean 1-x<0, so ln (1-x) would not exist. Therefore, x=-1.

2007-04-16 13:28:03 · answer #1 · answered by Pascal 7 · 0 0

1. You can clean this up a bit to get
3/2 log x = 17.5 and solve that, but I wonder if the 17 is also in the log term.

2. You can raise each side to the "eth" power to get (1-x)(3-x)=8. This gives you a quadradic which you can solve "the usual way".

2007-04-16 20:26:17 · answer #2 · answered by cattbarf 7 · 0 0

1) Use log rules:
log(sqrt(x^3))-17=1/2
log(x^(3/2))-17=1/2
(3/2)log(x)-17=1/2
(3/2)log(x)=17.5
log(x)=11.66
x=4.64158 times 10 to the 11th

2)
ln(1-x)+ln(3-x)=ln(8)
ln((1-x)/(3-x))=ln(8)
(1-x)/(3-x)=8
1-x=8*(3-x)
1-x=24-8x
-23=-7x
x=3.2857

2007-04-16 20:25:02 · answer #3 · answered by Ooze90 3 · 0 0

fedest.com, questions and answers