For some of my math i just cant figure out what i have to do just to start

Any help or review to show me how to do some would be great?

here is a link to the questions

http://www.math.unb.ca/ready/paper/

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- August 28th 2006, 08:15 AMasdfghjkl[SOLVED] calc? ulate this fractions
For some of my math i just cant figure out what i have to do just to start

Any help or review to show me how to do some would be great?

here is a link to the questions

http://www.math.unb.ca/ready/paper/ - August 28th 2006, 08:30 AMCaptainBlackQuote:

Originally Posted by**asdfghjkl**

But I see no reason for not showing you how to do a selection of these.

1a. Simplify: .

First if is a common factor of the top or bottom of a

rational expression like this, factor it out:

.

Now look for terms which are the difference of two squares as we know

that , here we have such a term, so:

Now we check if we can cancel any terms, in this case we check if:

,

has one or more of , or

as factors. The first obviously is not a factor, if the second was a factor

then substituting into the expression would simplify to 0,

it does not so id not a factor of .

Now if the last candidate is a factor substituting into the

expressions would simplify to zero, which in this case it does, and by trial

and error we find:

, so now we have:

Finally cancel common terms to get:

RonL - August 28th 2006, 08:44 AMCaptainBlack
Don't make duplicate posts in a number of forums, it confuses and wastes the

time of the helpers who cannot tell if a question has been answered elsewhere.

Other thread deleted.

RonL - August 29th 2006, 05:05 AMCaptainBlackQuote:

Originally Posted by**asdfghjkl**

Now remember what we said earlier about the difference od two squares:

If we put and , we have:

So if we now multiply the top and bottom of by we don't change its value so:

RonL - September 2nd 2006, 03:59 AMCaptainBlack
4a. Solve for x (without using a claculator)

, so:

.

Therefore equating exponents , and so .

Can also be done by taking logs to the base 5:

but , so we are back to where we were, and

RonL - September 2nd 2006, 04:17 AMCaptainBlack
5a. Simplify:

.

Here the first things we need are some of the basic laws of logarithms:

,

and:

.

Now:

Finally we need to recall how to factorise the difference of two squares to get:

RonL