Domain of definition of the function f(x,y)=x^y

In summary, the conversation discusses the domain of definition for the function f(x,y)=x^y. The solution states that the function is defined for x=0, y≠0 because zero to any power (other than the zero power) is zero. The speaker also mentions that for x^y=exponential (y*ln(x)), x>0. However, another person clarifies that it is actually the other way around, meaning that if x>0, then ln(x) exists and the function is defined.
  • #1
Amaelle
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Homework Statement
find the domain of definition of the function f(x,y)=x^y
Relevant Equations
the domain of definition of the function
Good day
as said in the title i need the domain of definition of of the function f(x,y)=x^y
for me as x^y=expontial (y*ln(x)) so x>0

but the solution said more than that
x^y.png


I really don't understand why we consider the case (0,y) in which while should be different from 0, because I will never have an x=0?

many thanks in advance
 
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  • #2
Apparently :rolleyes: the function is defined for ##x=0, \ y\ne 0## :
because zero to any power (other than the zero power) is zero

Amaelle said:
for me as x^y=expontial (y*ln(x)) so x>0
It is the other way around: IF ##x>0## THEN ##\ln(x)## exists AND ...
 
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Likes Amaelle
  • #3
thanks a lot!
 

1. What is the domain of definition for the function f(x,y)=x^y?

The domain of definition for this function is all real numbers for both x and y, except for when x = 0 and y is a negative number. In this case, the function is undefined because raising 0 to a negative power results in division by 0, which is undefined.

2. Can the function f(x,y)=x^y be defined for complex numbers?

Yes, the function can be defined for complex numbers. In this case, the domain of definition is all complex numbers for both x and y, except for when x = 0 and y is a non-integer. This is because raising 0 to a non-integer power results in a complex number.

3. What happens to the function f(x,y)=x^y as x and y approach infinity?

As x and y approach infinity, the function will also approach infinity. This is because the value of x^y increases exponentially as both x and y increase.

4. Is the function f(x,y)=x^y continuous?

Yes, the function is continuous. This means that as x and y approach a certain value, the value of the function will also approach that same value.

5. Can the function f(x,y)=x^y have a negative value?

Yes, the function can have a negative value. This occurs when the base, x, is a negative number and the exponent, y, is an odd integer. In this case, the result will be a negative number. However, if y is an even integer, the result will be positive.

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