# I need help on different quotient

• Jan 26th 2009, 01:28 PM
lsnyder
I need help on different quotient
F(x)= 1/(x+6).

I know the formula is F(x+h) -F(x)/ h.

Yet it goes in more detail saying to simplify the form -1/B to B=?
• Jan 26th 2009, 01:59 PM
Jhevon
Quote:

Originally Posted by lsnyder
F(x)= 1/(x+6).

I know the formula is F(x+h) -F(x)/ h.

Yet it goes in more detail saying to simplify the form -1/B to B=?

$\frac {f(x + h) - f(x)}h = \frac {\frac 1{x + h + 6} - \frac 1{x + 6}}h$

now combine the fractions in the numerator, and see what cancels
• Jan 26th 2009, 02:12 PM
lsnyder
i keep getting h/h, which is wrong on my homework.
• Jan 26th 2009, 02:25 PM
Jhevon
Quote:

Originally Posted by lsnyder
i keep getting h/h, which is wrong on my homework.

really?

what did you get for $\frac 1{x + h + 1} - \frac 1{x + 1}$ ? it should be clear that the answer will not be h as you claim.
• Jan 26th 2009, 02:26 PM
lsnyder
wouldn't it be just h? or did i miss something?
• Jan 26th 2009, 02:30 PM
Jhevon
Quote:

Originally Posted by lsnyder
wouldn't it be just h? or did i miss something?

have we forgotten how to add fractions?

$\frac 1{x + h + 1} - \frac 1{x + 1} = \frac {-h}{(x + 1)(x + h + 1)}$

which means...?
• Jan 26th 2009, 02:37 PM
lsnyder
okay i understand except where did -h come from?
• Jan 26th 2009, 02:41 PM
Jhevon
Quote:

Originally Posted by lsnyder
okay i understand except where did -h come from?

i added the fractions, there are several ways to do this, pick your favorite method. finding the common denominator etc etc etc