Question

i dont understand this problem:
8^(x/2)=4^(x+1)
anyone know?

Answer 1

i ASSume you want to solve for x?

Answer 2

i guess, the questions says to solve

Answer 3

asks*

Answer 4

right - this equation has x in the exponent (power) so we take logs of both sides:

ln 8^(x/2) = ln 4^(x+1)

by the laws of logarithms:

(x/2) ln 8 = (x+1) ln 4
(x/2) = ((x+1) ln4) / ln 8)
(x/2) / (x+1) = ln4) / ln 8)

(x/2) / (x+1) = 2/3

excuse me - i must leave the room - be back later to complete it

Answer 5

no problem.
thanks for your reply in the meantime, jimmyrep

Answer 6

so whats left is to solve this last equation

3x = 4(x+1)
3x = 4x + 4

x = -4

Answer 7

the 3 main laws of logarithms are

log x + log y = log xy

log x - log y = log (x/y)

log (x^y) = y log x

Answer 8

thanks jimmyrep