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# Please Can someone explain these logs watch

1. From Jan 05 Paper

b) log2 (2x+1) = log2 x = 2

log2 (2x+ 1 ) / x = 2

This is the part i dont get

2x + 1/ x = 2^2 = 4

How do you get rid of the log2 and get 4 on the other side, can someone please explain that?

and How does the change of base rule turn 6logx 5 into 6/log5 x

thank you so much, i dont understand these at all so can you please explain it as fully as possible, much appreciated
2. When you have something of the form:

logab = c, then you get:

ac = b

It's pretty much the fundemental rule of logs.
3. for the first part , to get rid of log2 you do 2(to the power of) to both sides

so 2^log2(2x-1/x) just = (2x-1/x) and 2^2 = 4

not sure for part 2
4. Change of base...

6logx5 = 6[log55 / log5x] = 6/log5x

Generally, logab = logcb / logca

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