HP HP-15C

Section 2: Working With [7F] 53
Keystrokes Display
Q][/l) 1 9.995 -01 Integral over (0,10)
calculated in | SCI 13.
I 2 + | 1.000 00 Sum approximation and
its uncertainty in registers
R3 and R5.
\x\y\1 -04 Uncertainty of
approximation.
IR+IIR+I 1.000 01 Roll down stack until
upper limit of first
integral appears in X-
register.
228 228 Keys upper limit of second
integral into X-register.
Upper limit of first
integral is lifted into Y-
register, becoming lower
limit of second integral.
[TirscilO 2. 02 Specifies [SO]0 display
format for a quick
calculation over (10, 228).
— If the uncertainty of the
approximation turns out
/— not to be accurate enough,
you can repeat the
approximation in a
display format specifying
more digits.
^ EC/31 5. -04 Integral over (10,228)
calculated in|SCl|0.
,/~ [?1|SCI|3 5.328 -04 Changes display format
back to | SCI 13.
|x$y| 7.568 -05 Checks uncertainty of
-^ approximation. Since it is
less than the uncertainty
,— of the approximation over
the first subinterval,
| SCI | 0 yielded an
approximation of
sufficient accuracy.