When is -x^-4 equal to (-x)^-4?

[pandamonium786]

Homework Statement

For which non-zero value of x is the equation -x^ -4 = (-x)^ -4 true? Explain.

Homework Equations

None. Other than applicable exponent laws.

The Attempt at a Solution

I know how to use the guess and check method. But I was wondering how to reach the answer faster and how to solve this problem.

 

[LittleMrsMonkey]

There is no value for which it is true.Try and prove it.

 

[pandamonium786]

There is no value for which it is true.Try and prove it.

i understand that but could negative numbers like -1 work?

 

[LittleMrsMonkey]

If you raise any negative to an even power(like -4) it gives something positive.

 

[LittleMrsMonkey]

Try to simplify the equation,you will get to -1=1,which of course isn't true.So the equation isn't true for any x.

 

[pandamonium786]

Try to simplify the equation,you will get to -1=1,which of course isn't true.So the equation isn't true for any x.

Thanks again :D

 

[HallsofIvy]

i understand that but could negative numbers like -1 work?

How can you possibly say "I understand" that no value works and then ask if a negative value works?