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# C3 logs watch

1. Work out the inverse.

Do i use the base changing formula for this? As i obviously need to get it to the base e, can someone show me how please.

Cheers
2. Make it
y = logV2(3x+1)
2^y = (3x +1)
(2^y) - 1 = 3x
((2^y) - 1) / 3 = x

so the inverse is ((2^x) - 1) / 3

That's what I'd do anyway. Hope it helps/is right!
I have my Core 3 exam tomorrow, and I'm bricking it!!!
3. (Original post by dani_lou)
Make it
y = logV2(3x+1)
2^y = (3x +1)
(2^y) - 1 = 3x
((2^y) - 1) / 3 = x

so the inverse is ((2^x) - 1) / 3

That's what I'd do anyway. Hope it helps/is right!
I have my Core 3 exam tomorrow, and I'm bricking it!!!
It is right, yes.
4. (Original post by generalebriety)
It is right, yes.
Thank god for that!!!
I may still have a chance tomorrow then!!!
5. (Original post by dani_lou)
Make it
y = logV2(3x+1)
2^y = (3x +1)
(2^y) - 1 = 3x
((2^y) - 1) / 3 = x

so the inverse is ((2^x) - 1) / 3

That's what I'd do anyway. Hope it helps/is right!
I have my Core 3 exam tomorrow, and I'm bricking it!!!
Oh right cheers dani, is there any rule/formula for this? Because i used to vaguely remember me doing this for C2, but wouldn't know why lol.
6. Well... The rule for finding the inverse, as far as I know, is tow make f(x) "y", and then re-arrange to make x the subject. Then you make all the ys xs, and that's your inverse.

The log rule is that log-to-the-base-x (I can't be bothered to draw pictures!) is cancelled out by X^. If that makes any sense. You can only use e when you have ln (natural log).
7. (Original post by dani_lou)
Well... The rule for finding the inverse, as far as I know, is tow make f(x) "y", and then re-arrange to make x the subject. Then you make all the ys xs, and that's your inverse.

The log rule is that log-to-the-base-x (I can't be bothered to draw pictures!) is cancelled out by X^. If that makes any sense. You can only use e when you have ln (natural log).
No, not that lol ... i meant getting the base of the logs and making it (2^y)
8. (Original post by Totally Tom)
Thanks Tom, picture drawing genius.
To Doji... What he said! ^ ^ ^
9. (Original post by Totally Tom)
Oh thats it! cheers thanks tom

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