- #1

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## Homework Statement

I need to prove the identity:

(

**a**×

**b**)[itex]\cdot[/itex](

**c**×

**d**)= (

**a**[itex]\cdot[/itex]

**c**)(

**b**[itex]\cdot[/itex]

**d**)-(

**a**[itex]\cdot[/itex]

**d**)(

**b**[itex]\cdot[/itex]

**c**)

using the properties of the vector and triple products:

## Homework Equations

**a**×(

**b**×

**c**)=

**b**(

**a**[itex]\cdot[/itex]

**c**)-

**c**(

**a**[itex]\cdot[/itex]

**b**)

**a**[itex]\cdot[/itex](

**b**×

**c**)=

**c**[itex]\cdot[/itex](

**a**×

**b**)=

**b**[itex]\cdot[/itex](

**c**×

**a**)

## The Attempt at a Solution

I really don't know where to begin. I need to prove this identity simply so I can use it on a problem, and I know it CAN be proven using these identities from the triple products, but I'm lost on how to attempt such a proof.