Solve Where applicable find an exact answer first then appro
Solve. Where applicable, find an exact answer first, then approximate to the nearest thousandth. 3^x+1 = 2^5x-2 log(x + 3) = 1 m- logx logx - log(x - 2) = log 4
Solution
a) 3^(x+1) = 2^(5x -2)
Taking log on both sides:
ln3^(x+1) = ln2^(5x -2)
(x+1)ln3 = (5x -2)ln2
x( ln3 -5ln2) = -ln2 -ln3
x =- (ln2 +ln3)/(ln3 -5ln2)
= 0.756
b) log( x+3) = 1 - logx
log(x+3) +logx =1
log(x(x+3)) = 1
x(x+3) = 10
x^2 +3x -10=0
use quadratic root formula:
x= (-3 +/- sqrt(9 +4*10)/2
= (-3 +/- 7)/2
= -5 , 2
Solution : x = -5 , 2
c) logx -log(x-4) =log4
log(x/(x-4) = log4
equate the argument inside the log:
x/(x-4) = 4
x= 4x -16
-3x = -16
Solution : x= 16/3
