Mr. Khan,

In general - with separation.

Trp, yes, if you excite @ 300nm. Then you'll get mostly Trp fluorescence

Tyr - problematic. Its excitation wavelengths coincides with those of Trp & Phe. Still, you can excite @ ~280 nm and observe fluorescence spectrum in the range 300-350 nm. Just remember that Trp fluorescence spectrum is also between 320-360 nm, so there will be some overlap. Also, as mentioned above, the Tyr fluorescence spectrum intensity will be influenced by FRET to Trp.

So the question is how narrow can you excitation linewidth be in order to precisely excite just Trp @ 300nm?