Problem

Is the function f:RR,f(x)=x3 surjective?

Answer

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Answer

Step 4: Since y3 is defined for all y in R, we can conclude that for every y in R, there exists an x in R such that f(x)=y.

Steps

Step 1 :Step 1: To determine if a function is surjective, we need to show that for every element y in the codomain R, there exists an element x in the domain R such that f(x)=y.

Step 2 :Step 2: Let's take an arbitrary y in R. We need to find an x such that f(x)=y. So we solve the equation x3=y for x.

Step 3 :Step 3: By taking the cube root on both sides, we find that x=y3.

Step 4 :Step 4: Since y3 is defined for all y in R, we can conclude that for every y in R, there exists an x in R such that f(x)=y.

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