HP 35s HP 35s scientific calculator - User Guide - Page 133

4 H H   Terminates and displays the equation. Checksum and length. It seems reasonable that either a tall, narrow box or a short, flat box could be formed having the desired volume. Because the taller box is preferred, larger initial estimates of the height are reasonable. However, heights greater than 20 cm are not physically possible because the metal sheet is only 40 cm wide. Initial estimates of 10 and 20 cm are therefore appropriate. Keys: H H Display: value Description: Leaves Equation mode. Stores lower and upper limit guesses. Displays current equation. Solves for H; prompts for V. Stores 7500 in V; solves for H. Now check the quality of this solution - that is, whether it returned an exact root - by looking at the value of the previous estimate of the root (in the Y-register) and the value of the equation at the root (in the Z-register). Keys:   Display Description: This value from the Y-register is the estimate made just prior to the final result. Since it is the same as the solution, the solution is an exact root. This value from the Z-register shows the equation equals zero at the root. Solving Equations 7-11