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
There is a lot here, and it would be a mistake for us to do them all for you.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:
2a. Rationalise the denominator of: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: