Question

Ive been staring at this problem for like a half hour now and I cant figure out where to even begin...

log(base x)4 + log(base 8)squareroot(x) = 4/3

solve for x

any help appreciated

Answers

Reiny
Have you come across the property
log<sub>a</sub>b = log b/log a ?

log<sub>x</sub>4 + log<sub>8</sub>squareroot(x) = 4/3

log<sub>x</sub>4 + (1/2)log<sub>8</sub>(x) = 4/3

log4/logx + (1/2)logx/log8 = 4/3
let logx = t
log4/t + t/(2log8) = 4/3

multiply each term by (6log8)t to get the quadratic
6log4(log8) + 3t^2 = 8log8(t)

After re-arranging, use the quadratic formula to solve for t, after that sub back into logx = t to get x

check my steps, easy to make typos here.

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