HP 20B User Manual page 24

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to scroll through the menu items, starting with Trigonometry. The Trigonometry, Hyperbolic, and Probability items
Press
have sub-menus. Press
O
Press to cancel the Math menu and return to current work. Press
For an example using the math menu to calculate Sin -1 (0.5), see Table 2-5.
Figure 8 The Menu Map for the Math Menu
I
with these items displayed to access the functions within the sub menus.
:s
24
Mathematical Calculations
to return to the top of the Math menu.