HP 35s Instruction Manual page 6
Using rpn mode
Hide thumbs
Also See for HP 35s:
- User manual (382 pages) ,
- Quick start manual (60 pages) ,
- Instruction manual (8 pages)
Advertisement
hp calculators
HP 35s Using RPN Mode
2Ï10)
A
nswer:
Two to the power 10 is 1,024, often called 1k in computing.
works exactly like the arithmetical operators and is often considered to be one of them. Most other two-number
)
functions work this way too. These are the root (or involution) function ¹', quotient ¹g2 (b) and
remainder ¹g3 (`), combinations ¹x and permutations º{.
W
orking with complex numbers, with pairs of numbers representing rectangular or polar coordinates and with pairs of
numbers in statistical operations are described in training aids on these subjects.
E
xample – which stepladder?
S
ome people will wonder why RPN is worth using if algebraic mode and Equation mode work the way expressions are
printed. Here is an example to show how RPN mode is useful and fast in solving step-by-step problems where there is
no formula, and where the next calculation depends on the result of the previous one.
E
xample 7:
You need to fix a tile that has fallen off your roof. The roof is 28 feet up, and you have a stepladder that is
29 feet long. You could also borrow your neighbor's 38 foot ladder. Is either ladder good for the job? You
could try leaning each one in turn against the roof and seeing which is better, but it's raining, so why not
work it out first on your HP 35s by seeing what angle each ladder will make with the vertical when you lea
it against the roof?
S
olution:
First try it for your own ladder. Switch to RPN mode if it is not set. Enter the ladder length:
29Ï
Then enter the height and divide so you can get the angle, 28¯. You get 1.04. That can not be right;
sines and cosines should be smaller than 1. UseºÍ¸ºÍ to get the numbers back, then
w to swap them. Now press ¯ to divide them again, in the right order, and see 0.97.
Actually, pressing , would get the same result, making the correction more quickly. Anyway, this is the
sine of the angle between the ladder and the vertical. Or is it the cosine? Press ºi and see the
answer, 74.91 degrees. No, that is not right, it must be the arc cosine that you need. You could press
~ºÍ again to undo the arc sine, but it is as quick to press k, then ºl.
Your ladder would be only 15 degrees away from the vertical. That is uncomfortably steep. So try the same
calculation for your neighbor's 38 foot ladder.
Type 28Ï38¯ then ºl. This time the answer is 42.54 degrees. The ladder
would be at a rather shallow angle and might slip away as you stand on it.
A
nswer:
Neither ladder is really suitable. Maybe you should ask some other neighbors if they would lend you a
ladder with a better length. What would be a good length? 30 degrees would probably still be too much,
hp calculators
- 6 -
Figure 9
HP 35s Using RPN Mode - Version 1.0
n
Advertisement
