Problem

Given the function f:RR defined as f(x)=x2, determine if this function is surjective (onto).

Answer

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Answer

Step 4: Therefore, for any real number b<0, there is no real number a such that a2=b. This means that the function f(x)=x2 is not surjective.

Steps

Step 1 :Step 1: A function f:AB is said to be surjective (onto) if for every bB, there exists an aA such that f(a)=b.

Step 2 :Step 2: In our case, A=B=R, the set of all real numbers, and f(x)=x2.

Step 3 :Step 3: For the function to be surjective, every real number should be the square of some real number. But we know that the square of any real number is always non-negative, i.e., x20 for all xR.

Step 4 :Step 4: Therefore, for any real number b<0, there is no real number a such that a2=b. This means that the function f(x)=x2 is not surjective.

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