HP 15C Shortcut for (Complex Absolute Value)

[Gamo]

Very short steps to calculate Complex Absolute Value with (Add or Subtract)
This work on any Scientific Calculator that have [→P] function

Formula: │a+ib│ = √(a^2+b^2)

Example: │3 + 4i│ = 5

Steps:

1. (b) ENTER --->4
2. (a) →P ------->3

Gamo

[Paul Dale]

Why not just use complex mode on the 15C?


Pauli

[Gamo]

Thanks Paul Dale
Forgot to mention that this is a shortcut way of doing it.

[Dieter]

(10-27-2017 08:55 AM)Paul Dale Wrote:  Why not just use complex mode on the 15C?

FTR: this also works nicely on the 35s (which has no dedicated P↔R functions):
3 [i] 4 [ABS] => 5.

On the other hand the →P method mentioned by Gamo is quite handy for chain calulations. Sometimes the sum of the squares is the square of a sum, i.e. s² = a²+b²+c²+... For instance in photography: Suppose you have the f-number readings for three individual light sources shining on a subject, say f/8, f/11 and f/2,8. Then the value for the sum of all three can be determined easily with

8 [ENTER] 11 [→P] 2,8 [→P] => f/14

The same method can be used for the guide numbers of multiple flashguns firing in the same direction.

Dieter