# Homework Help: Commutator [x,T]?

1. Jun 26, 2014

### kq6up

1. The problem statement, all variables and given/known data

Find $[\hat{x},\hat{T}]$.

2. Relevant equations

$[\hat{x},\hat{T}]=\hat{x}\hat{T}-\hat{T}\hat{x}$

3. The attempt at a solution
I wind up with $\frac{i\hbar}{m}\hat{p}$. Did I do good, boss?

Chris

2. Jun 26, 2014

### Dr Transport

Define $\hat{T}$

3. Jun 26, 2014

### kq6up

It is the kinetic energy operator. p^2/2m.

Chris

4. Jun 27, 2014

### CAF123

I am not sure if this is the way you did it, but using the fact that $[A,BC] = B[A,C] + [A,B]C$ for operators $A, B$ and $C$, the result follows in one line using the canonical commutation relations for $\hat{x}$ and $\hat{p}$.