Are x+x^2 and u+u^2 the same function? If x and u are for all real numbers? A- these are the same function B- If x and u are two different numbers, the functions are different C- there is not enough information to answer this question.

Respuesta :

Answer:

(a) These are the same function

Step-by-step explanation:

Given

[tex]x + x^2[/tex] and [tex]u + u^2[/tex]

Required

Are they the same?

Yes, they are the same function and this is proved below.

[tex]x + x^2[/tex]

Represent as a function:

[tex]f(x) = x + x^2[/tex]

[tex]u + u^2[/tex]

Represent as a function

[tex]f(u) = u + u^2[/tex]

Let x = u

Substitute u for x in [tex]f(x) = x + x^2[/tex]

[tex]f(u) = u + u^2[/tex]

This implies that:

[tex]f(x) = f(u)[/tex]

[tex]x + x^2 =u + u^2[/tex]

PS: The information that x and u are real numbers are for all real numbers; So, we can not assume that x and u are different numbers

Hence:

(b) and (c) are wrong