Notation Confusion in Linear Transformations

AI Thread Summary
The notation {f∈F(ℝ,ℝ): f(3)=5} indicates that 'f' is a function mapping real numbers to real numbers, specifically defined such that f(3) equals 5. This does not imply that the function's range encompasses all real numbers; rather, it suggests that the range is a subset of the real numbers. Understanding this distinction is crucial for interpreting linear transformations correctly. The confusion often arises from the assumption that the notation implies a broader range than it actually does. Clarifying these notational meanings is essential for grasping the concepts of linear transformations.
Offlinedoctor
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I'm just having trouble understanding some of the notations given, when attempting questions such as the following:

{f\inF(ℝ,ℝ): f(3)=5}.

Is it just saying that, the function 'f' spans all real values?
 
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Offlinedoctor said:
I'm just having trouble understanding some of the notations given, when attempting questions such as the following:

{f\inF(ℝ,ℝ): f(3)=5}.

Is it just saying that, the function 'f' spans all real values?
That is saying that f is a function from the set of real numbers to the set of real numbers, such that when x= 3, f(x)= 5.

It does NOT necessarily mean that the range of f includes all real numbers, just that the range is some subset of the real numbers.
 
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Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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