# Thread: Probably an easy one for you guys but help needed :-)

1. ## Probably an easy one for you guys but help needed :-)

Background, i have started doing an HNC in Mech Eng through work. It was my choice so i have the motivation to plug away at it.

I have had a gap in my life of 16 years of doing no maths at all. I was never that great at it in the first place but i have worked extremely hard this year to get it up to a decent standard but i do notice there are gaps in my knowledge.

So to my problem, i am working out an equation i do not know why a certain steps works the way it does.

it is as follows = working out for t.

e^-ct=1-(p/p0) The next step is the problem. It becomes -ct log e = log (p0-p/p0)

Why does transforming the right side give me what it does? Its not the log part, that's easy its the 1- part.

Thanks guys

2. ## Re: Probably an easy one for you guys but help needed :-)

It's just getting a common denominator:

$1-\frac{p}{p_0}=\frac{p_0}{p_0}-\frac{p}{p_0}=\frac{p_0-p}{p_0}$

3. ## Re: Probably an easy one for you guys but help needed :-)

ok, makes sense :-) Thanks

4. ## Re: Probably an easy one for you guys but help needed :-)

Glad to help, and welcome to the forum!