challenge question melt your mind (1 Viewer)

[jordon1]

Been trying to work this one out for ages found it in a old HSC test

2lnx = ln(4x+5) and the answer is x = 5

can anyone reveal how this is to be done

 

[Squar3root]

ln(x^2) = ln(4x +5)

x^2 = 4x + 5

x = -1 or x = 5

domain(ln) > 0

hence x = 5

was not a challenge and my mind is the same consistency as before i solved it