HP 40gs User Manual page 214

SIMPLIFY
XNUM
XQ
14-32
Typing:
SINCOS(EXP(i·X))
gives after turning on complex mode, if necessary:
cos(x) + i · sin(x)
Simplify
SIMPLIFY simplifies an expression automatically.
Typing:
⎛
SIMPLIFY
⎝
gives, after simplification:
2
− 2
4 · cos(x)
Evaluation of reals
XNUM has an expression as a parameter.
XNUM puts the calculator into approximate mode and
returns the numeric value of the expression.
Typing:
XNUM(√2)
gives:
1.41421356237
Rational approximation
XQ has a real numeric expression as a parameter.
XQ puts the calculator into exact mode and gives a
rational or real approximation of the expression.
Typing:
XQ(1.41421)
gives:
66441
-------------- -
46981
( ⋅ )
SIN 3 X + SIN 7 X
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
( ⋅ )
SIN 5 X
Computer Algebra System (CAS)
( ⋅ )
⎞
⎠