How do you solve logₐx^10-2logₐ(x^3/4)=4logₐ(2x)?

1 Answer
Nov 27, 2015

The equation is an identity, and therefore it has an infinite number of solutions.

Explanation:

log_a(x^10)-2log_a(x^3/4)=4log_a(2x)
let's work the left side(LS) only and simplify it:
LS=log_a(x^10)-log_a(x^6/16)
LS=log_a{(x^10)/[(x^6)/(16)]}
LS=log_a(16x^4)
LS=log_a[(2x)^4]
LS=4log_a(2x)
Now:
RS=4log_a(2x)
:.LS=RS
Within the basic laws and valid domain of logarithms, i.e: a!=1 and x>0, the original equation is an identity, and therefore it has an infinite number of solutions.