1. May 27, 2014

### Digital Genius

1. The problem statement, all variables and given/known data

* "/" means divided by *

1/a , 1/b , 1/c are consecutive terms in an AS, where a,b,c ε R\0. (whatever that means haha)

express b in terms of a and c. give your answer in its simplest form.

*thats all it says*

2. Relevant equations

there are none :)

3. The attempt at a solution

sorry but i have absolutely no clue and thats why im posting this haha

2. May 27, 2014

### Digital Genius

ok nevermind guys sorry, i just found that i did do the question haha................

anyways for those who wanna know its like this...

T1, T2, T3
1/a, 1/b, 1/c = AS
T2-T1=T3-T2
T2+T2=T3+T1
1/b + 1/b = 1/c + 1/a
2(1/b)=1/ac
2b=1/(1/a - 1/c)
b= 2 1/(1/a - 1/c)

and thats it i think..

3. May 27, 2014

It's wrong.
$\frac{1}{c}+\frac{1}{a} \neq \frac{1}{ac}$
You have some algebra problems there. I get a different answer. Try again
I have coloured the wrong parts in red.

4. May 27, 2014

5. May 27, 2014

### Digital Genius

so what is the rest of it that you got? because im stumped haha

6. May 27, 2014

Let's start from the original question.
$\frac{1}{a},\frac{1}{b},\frac{1}{c}$ . Express b interms of a and c.
As you showed, $\frac{1}{b}-\frac{1}{a}=\frac{1}{c}-\frac{1}{b}$
So $\frac{1}{b}+\frac{1}{b}=\frac{1}{c}+\frac{1}{a}$
$\frac{2}{b}=\frac{1}{c}+\frac{1}{a}$

Simplify $\frac{1}{c}+\frac{1}{a}$ then solve for b.

7. Jun 2, 2014

### Digital Genius

ok thanks haha, i have it now, i even checked with my A- standard student/friend :D