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# Mark schemes are useless!!!! - question. watch

1. Jeez - you find the mark scheme and you still dont get it (you being me!)

Mark scheme states that:

y = 3 ln (1/3) + 1/(1/3) = 3 - 3 ln 3

since when? why has the first 1/3 changed to a 3 ? and where has the minus sign come from?

Laura xxxx
2. 1 divided by 1/3 = 3.

1/3 = 3^-1.
So 3ln(1/3) can be written 3ln(3^-1) which= -3ln3

So 3ln(1/3) + 1/(1/3) = 3-3ln3
3. (Original post by Laura_M)
Jeez - you find the mark scheme and you still dont get it (you being me!)

Mark scheme states that:

y = 3 ln (1/3) + 1/(1/3) = 3 - 3 ln 3

since when? why has the first 1/3 changed to a 3 ? and where has the minus sign come from?

Laura xxxx
ln(1/3)=ln(3^-1)=-ln3.
It's one of the properties of logarithms: ln(a^b)=blna.
4. Or you can use the log laws,

ln(1/3) = ln1-ln3 = -ln3

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