SOLUTION: How can you restrict the domain of f(x)=3x^2 such that it's inverse will be a function.

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Question 1078905: How can you restrict the domain of f(x)=3x^2 such that it's inverse will be a function.
Found 2 solutions by Boreal, MathLover1:
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
inverse of 3x^2
x=3y^2
y^2=x/3
y=+ sqrt (x/3)
Want the domain to be non-negative numbers.
graph%28300%2C300%2C0%2C10%2C-2%2C10%2C3x%5E2%2Csqrt%28x%2F3%29%29

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
f%28x%29=3x%5E2
find f%5E-1%28x%29 : recall that f%28x%29=y
y=3x%5E2.....switch x and y
x=3y%5E2
x%2F3=y%5E2
y=sqrt%28x%2F3%29
y=sqrt%28x%29%2Fsqrt%283%29
so, your inverse is f%5E-1%28x%29=sqrt%28x%29%2Fsqrt%283%29
domain:
should exclude x=0 value and domain is all non-negative real numbers
{ x element of R: x%3E=0 }