HP·38E/38C - Slide Rule Museum

60 Mathematical Functions
To raise a negative number to a positive or negative integer power, key
in the base number, press I CHS I, press IENTBltl, key in the integer power,
and press []J 0 .
Solve (_2)3:
Keystrokes
2 ICHSllENTEAtl
3[]J0
Display
-2.00
-8.00
With a negative base, if the exponent is an odd number, the answer will
be negative. If the exponent is an even number, your answer will be
positive:
(_2)2 = -2 x -2 = 4
(_2)3 = -2 x -2 x -2 = -8
You can also use 0 to raise 0 to a positive power; but of course,
your answer will always be zero.
The cube root of a number is that number raised to the 1/3 power.
Thus, -\In is the same as n1/3; the fourth root can be written as n il4 or
nO. 25 , etc.
Use the same keystroke sequence that you learned for exponentiation to
extract higher roots:
1. Key in the base number and press IENTBltl.
2. Key in the root desired, then press iIJ[ill .
3. Press []J 0 .
20
To solve V'lO (101/ 2 °):
Keystrokes
10 IENTBltl
20 iIJ [ill []J 0
15
Now, try Y22 (22 1 /15):
Keystrokes
22 IENTBltl
15 iIJ[ill []J 0
Display
10.00
1.12
Display
22.00
1.23