# Math help.

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God this shit again. Simplify the expression :-/ x(x^2 + 5)^-5 + x^2(x^2+5)^-4 God this is hard can someone help direct me somehow? I know i have asked questions on this before but I really cant figure this one out. Plz help.

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what things are common between the items on either side of the + sign...

-me

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ok the common things are (x^2+5).
EDIT:
I would think you would do something like this:
x(x^2+5)^-5 + x^2(x^2+5)^-4

((x^2+5)^-4) / ((x^2+5)^-5) = x^2+5
Then I think i would divide x^2 by x and that would be x so would it be:
x(x^2+5) = x^3+5x?

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What math course are you in..? I'd just raise the terms in the parentheses to the power, distribute in the x, and then add/subtract the terms. Your teacher should really be able to help you with this or a kid in your class.

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I'm in a precal class this is a prerequisite but I was never taught it and i'm trying to catch up. The teacher is lazy and never helps says she is busy.
x(x^2 + 5)^-5 + x^2(x^2+5)^-4
then we see that the like term is (x^2 + 5)^-5 then we divide it from both sides giving us:
x(1) + x^2 (x^2+5)
is that part right?
x^4 + 5x^2 + x?

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I'm goin to bed now but hey guys lemme know i'll be reading this in the morning to check if i got any replies. Seeya then.

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No. You can only divide through when equating it to something. What you do there doesn't work.

x(x^2 + 5)^-5 + x^2(x^2+5)^-4 != x(1) + x^2(x^2+5)
but
x(x^2 + 5)^-5 + x^2(x^2+5)^-4 = ((x^2 + 5)^-5)(x + x^2(x^2 + 5))

Are you sure you're working with the correct expression? It's awfully complex. The axiom program tells me the answer is
(5) -> x*((x^2 + 5)^(-5)) + (x^2)*((x^2+5)^(-4))                         4     2                        x  + 5x  + x   (5)  -------------------------------------------         10      8       6        4        2        x   + 25x  + 250x  + 1250x  + 3125x  + 3125

But that just looks like all it's done is expand it.

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Unfortuanately, since this doesn't equal anything you can't just divide off the like terms. You can only multiply or divide by one (or an expression that equals one), you can also add or subtract 0 (or expressions equaling zero). Because of this there aren't many options.

Try writing both values in rational form (as fractions), and then find the common demonimator.

Then rewrite as a single rational. Look for terms that can be reduced or rewritten into a form that allows for reduction (I didn't find any). The answer isn't pretty, but it is simplified.

Most of this is just mechanics, so make sure you understand the procedure of simplifying:

Write everything in standard notation (x^-n = 1/x^n)
Look for common terms
Rewrite in a more compact form
Repeat looking for common terms and simplfying and reducing
(Most importantly)--DO ONE STEP AT A TIME!!

As you gain proficiency you'll be able to group multiple simplifications together, but for practice or complicated problems, take it easy. Calculus is graded just as much on proper procedure as it is the correct answer.

Hope this helps...

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Start manipulating, using the rules of algebra.
When you begin to understand how they affect the expression, start moving the equation into the required form.

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Quote:
 Original post by VlionStart manipulating, using the rules of algebra.When you begin to understand how they affect the expression, start moving the equation into the required form.

Exactly...

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