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I'm looking at the solution of a question but I don't understand it:

how do I get from (lnx/ln2) +(lnx/2ln2) = 1

to (3lnx/2) = ln2

I'm confused about where the 3lnx came from and where did the 2ln2 go?

thanks!
Reply 1
Multiply both sides by ln2
Combine the terms in the left as a fraction

Posted from TSR Mobile
Original post by Krollo
Multiply both sides by ln2
Combine the terms in the left as a fraction

Posted from TSR Mobile


I multiplied both sides by ln 2 and got lnx + (lnx/2) = ln2

I tried to combine the terms on the left but I got 2lnx/2 = ln2

Where am I going wrong when combining the terms?

thanks
(edited 9 years ago)
Reply 3
Original post by HelloGoodbye
I multiplied both sides by ln 2 and got lnx + (lnx/2) = ln2

I tried to combine the terms on the left but I got 2lnx/2 = ln2

Where am I going wrong when combining the terms?

thanks


you don't need to multiply anything by ln 2.

You've basically got y+y2=3y2y + \dfrac{y}{2} = \dfrac{3y}{2} - that's where the '3' comes from :smile:

EDIT: obviously you do need to multiply by ln2 at the end to get the form they want, but it's not necessary to do it at the start :smile:
(edited 9 years ago)
Original post by HelloGoodbye
I multiplied both sides by ln 2 and got lnx + (lnx/2) = ln2

I tried to combine the terms on the left but I got 2lnx/2 = ln2

Where am I going wrong when combining the terms?

thanks


lnx+lnx2=3lnx2\ln x+\frac{\ln x}{2}=\frac{3\ln x}{2} !!!

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