Show that T preserves scalar multiplication - Linear Transformations

AI Thread Summary
The discussion focuses on proving that the linear transformation T preserves scalar multiplication, specifically showing that T(λx) = λT(x) for all λ in ℝ and x in ℝ². The initial proof attempt correctly identifies the cases when x₂ equals zero and when it does not, but lacks clarity in presentation. It is advised to separate the cases for better readability and to ensure that the proof is structured correctly. The suggestion includes handling the cases for λ being zero and non-zero distinctly. Clear formatting and case separation are essential for a rigorous proof.
NewtonianAlch
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Homework Statement



Let T:ℝ^{2}→ℝ be defined by
T\left(\begin{array}{c} x_{1} \\x_{2}\end{array}\right) = (0 if x_{2} = 0. \frac{x^{3}_{1}}{x^{2}_{2}} otherwise.)

Show that T preserves scalar multiplication, i.e T(λx) = λT(x) for all λ \in ℝ and all x \in ℝ^{2}

The Attempt at a Solution



T(λx) = T\left(\begin{array}{c} (λx_{1}) \\(λx_{2})\end{array}\right) = (λ0 = 0 if x_{2} = 0, or \frac{(λx_{1})^{3}}{(λx_{2})^{2}})
= λT\left(\begin{array}{c} x_{1} \\x_{2}\end{array}\right) = λ0 = 0 if x_{2} = 0, or
λ*\left(\begin{array}{c} (x_{1})^{3} \\(x_{2})^{2}\end{array}\right)

Is that a correct proof?

It's a bit hard to read because whenever I try to put a vector, it puts it into a new line.
 
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It's putting new lines wherever you try to put a vector because you are putting "bits and pieces" inside [ tex ] tags. Don't do that. Put entire equations inside [ tex ] tags.

Also do "x_2= 0" and "x_2\ne 0" separately. You have "x_2= 0" in two different places which makes it hard to read.

If x_2= 0, then \lambda x_2= 0 for any \lambda so T(\lambda x)= 0= \lambda T(x).

If x_2\ne 0, then \lambda x_2\ne 0 for any \lambda except \lambda= 0 so you should do two separate cases, \lambda= 0 and \lambda\ne 0, here.
 
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