Texas Instruments TI-89 Titanium User Manual page 273

If you want to convert to a unit other than the default, use the 4 conversion operator.
expression_unit1
To convert 4 light years to kilometers:
4_ltyr 4 _km
To convert 186000 miles/second to
kilometers/hour:
186000_mi/_s
Constants and Measurement Units
4 _unit2
2 4
For , press
4
_km/_hr
4
.
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