- #1
chwala
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- Homework Statement
- consider the function:
##f(x)=x^3+3x−1##
- Relevant Equations
- odd or even functions concept
##f(x)=x^3+3x−1##
##-f(x) \ne f(-x) ##, so ##f## is not an odd function.chwala said:My question is, ...is the question also analogous in asking whether the function is even or odd? in that case,
can one use ##f(-x)=-f(x)##? the function is not an even function because
##f(-x)=f(x)##
on the other hand,
##f(-x)=-x^3-3x-1##
##-f(x)=-x^3-3x+1##=-(x^3+3x)-1##...=-f(x)## looks a bit interesting...
Mark just confirm, last term##-1## is an even function? am not getting this...Mark44 said:If the given function had been ##f(x) = x^3 + 3x##, it's easy to show that this is an odd function by use of the definition. Additionally, both ##x^3## and ##3x##, taken as functions on their own, are odd functions (i.e., their own reflection across the origin), and their sum is also an odd function.
However, ##f(x) = x^3 + x - 1 ## is neither odd nor even, as has already been shown. The last term, ##-1##, taken on its own, is an even function, and this prevents ##f(x) = x^3 + x - 1 ## from being its own reflection across the origin and across the y-axis, so it is neither odd nor even.
ehm any constant number can be considered to be function of any variable, for example -1 can be considered to be a constant function of x, ##g(x)=-1## and also a constant function of z ##h(z)=-1##.chwala said:ok, i will take this with a grain of salt, new to me . ##g## is a function of ##x##, of which clearly ##-1## is not. I guess maybe i need to check more on this delta.
chwala,chwala said:ok, i will take this with a grain of salt, new to me . ##g## is a function of ##x##, of which clearly ##-1## is not. I guess maybe i need to check more on this delta.
An odd function is a mathematical function that satisfies the property f(-x) = -f(x) for all values of x. This means that when you substitute a negative value for x, the output of the function will be the negative of the output when you substitute the positive value of x.
An even function is a mathematical function that satisfies the property f(-x) = f(x) for all values of x. This means that when you substitute a negative value for x, the output of the function will be the same as the output when you substitute the positive value of x.
To determine if a function is odd or even, you can substitute -x for x in the original function and simplify. If the resulting function is the negative of the original function, then the function is odd. If the resulting function is the same as the original function, then the function is even.
Odd and even functions are important in mathematics because they exhibit certain symmetry properties that can help simplify calculations and solve equations. They also have specific properties that make them useful in applications such as signal processing and physics.
No, a function cannot be both odd and even. A function can only satisfy one of the properties of odd or even functions, not both. However, there are functions that are neither odd nor even, and these are called neither odd nor even functions.