Math Is Fun Forum

4littlepiggiesmom

Member

Registered: 2006-01-09

Posts: 42

simplifing expressions with no negatives?? mom need help please!!

y(x^-3/y^-5)^-1  *  x(y^3/x^-3)^-3

I'm really lost but have gotten two answers?? 1 isx^6
the other is x^12/y^12

I doubt either are right but I don't knowe what to do about the first letter because I alwasy end up with (an example not the actual factors) x/y^-2/x^1 and don't know what to do next????

Tigeree

Member

Registered: 2005-11-19

Posts: 13,883

Re: simplifing expressions with no negatives?? mom need help please!!

how many toes do u have ?

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4littlepiggiesmom

Member

Registered: 2006-01-09

Posts: 42

Re: simplifing expressions with no negatives?? mom need help please!!

not enought to count on but 8 sheet f paper later /I have come up with 1/x^5y^13 is that getting closer?

irspow

Member

Registered: 2005-11-24

Posts: 1,055

Re: simplifing expressions with no negatives?? mom need help please!!

First thing is first.  A negative power is just the reciprocal of the positive power.  The reciprocal is just like flipping a fraction up-side down.  Example;  x^-2 = 1/x^2.

   Next, when you multiply variables with different powers, you keep the variable and add the powers together.  Ex;  (x^3)(x^2) = x^5.

   Last, when you divide variables with different powers, you subtract the power that is in the denominator from the power that is in the numerator.  Ex;  x^5 / x^2 = x^3.

   If you understand all of that, then you should have no problem following this;

   Each successive line will further simplify the equation.

   y(x^-3/y^-5)^-1  ×   x(y^3/x^-3)^-3

   y[(1/x^3) / (1/y^5)]^-1   ×   x[y^3 / (1/x^3)]^-3

   y(y^5 / x^3)^-1   ×   x(y^3 x^3)^-3

   y(x^3 / y^5)   ×    x(1 / (y^3 x^3)^3)

   yx^3 / y^5   ×    x(1 / (y^9 x^9))

   x^3 / y^4    ×    x / (y^9 x^9)

   x^3 / y^4    ×    1 / (y^9 x^8)

  After multiplication;

  x^3 / (y^13 x^8)

  1 / (y^13 x^5)

  That's your answer.  And that is exactly what you posted above.  Correct!

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I am at an age where I have forgotten more than I remember, but I still pretend to know it all.