HP 40gs hp 40gs_user's guide_English_E_HDPMSG40E07A.pdf - Page 258

hp40g+.book Page 6 Friday, December 9, 2005 1:03 AM this case, you have to press expression. to select elements in the The following illustration shows how an expression can be viewed as a tree in the Equation Writer. It illustrates a tree view of the expression: (---5---x----+-----3 x---------1----) x+3 ÷ × + + - N ! × !N  # N Suppose that the cursor is positioned to the right of 3: • If you press once, the 3 component is selected. • If you press again, the selection moves up the tree, with x + 3 now selected. • If you press again, the selection moves up the tree, and now the entire expression is selected. • If you had pressed instead of when the cursor was positioned to the right of 3, the leaves of the branch get selected (that is, x + 3). • If you press again, the selection moves up the tree, and now the entire expression is selected. • If you now press , just the numerator is selected. • If you now press again, the top-most branch selected (that is, (5x + 3). • Continue pressing to select each top-most leaf in turn (5x and then 5). 15-6 Equation Writer