Let g: \mathbb{R} o \mathbb{R} be defined by g(x)=3x+2 . Evaluate the proof that g(x) is bijective. Proof:
Suppose
g(x)=g(y) . Then 3x+2=3y+2 . By subtracting 2 from
both sides, we have 3x=3y . Dividing by 3 , we have x=y .
So g is injective. Suppose y is a real number. Then y=3x+2 . So 3x=y-2 and hence x=(y-2)/3 . So g is surjective. Thus g is bijective.
Choose the most complete correct answer.

Question

Let    g: \mathbb{R} 	o \mathbb{R}  be defined by   g(x)=3x+2 .  Evaluate the proof that   g(x)  is bijective.  Proof: 
 Suppose
   g(x)=g(y) . Then   3x+2=3y+2 . By subtracting   2  from 
both sides, we have   3x=3y . Dividing by   3 , we have   x=y .
 So   g  is injective.  Suppose   y  is a real number. Then   y=3x+2 . So   3x=y-2  and hence   x=(y-2)/3 . So   g  is surjective.  Thus   g  is bijective.  
 Choose the most complete correct answer.

Answer

The proof is correct.

Answer

The result is false, but the proof is correct.

Answer

There is an error in showing   g  is injective.

Answer

There are errors in showing   g  is injective and in showing   g  is surjective.

Answer

There are no errors so far, but the proof needs another step.

Answer

There is an error in showing   g  is surjective.

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Let g: \mathbb{R} \to \mathbb{R} be defined by g(x)=3x+2 . Evaluate the ...

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