HP 40gs hp 40gs_user's guide_English_E_HDPMSG40E07A.pdf - Page 297

hp40g+.book Page 23 Friday, December 9, 2005 1:03 AM Solution 1 Start by defining G(X): DEF G X = 2 X 3 X 2 Now press : Press and to select the numerator and denominator, and then press . This leaves G(X) displayed: Finally, apply the TABVAR function: TABVAR and press a number of times until the variation table appears (shown above). The first line of the variation table gives the sign of g′(x) according to x, and the second line the variations of g (x). Note that for TABVAR the function is always called F. We can deduce, then, that g(x) increases over [0, 2]. If you had been in step-by-step mode, you would have obtained: F = -2----⋅---X-----+-----3X+2 Press to get the result at the right. Step-by-Step Examples 16-23