HP 35s User Manual page 258

This program uses the built–in integration feature of the HP 35s to integrate the
equation of the normal frequency curve. The inverse is obtained using Newton's
method to iteratively search for a value of x which yields the given probability Q(x).
16-12
Statistics Programs
Q ( x ) 0 5 .
y
x
x
1
x
∫
(( x x
e
2
x
"U pper tail"
area
Q [x]
2
) ) 2
dx