Lesson 2
The Arithmetic of Powers
Multiplication by addition, and division by subtraction
Page 43
Your answer :
(47)/(42) = 45
(bm)/(bn) = b(m − n)
(74)/(72) = 49
(39)/(33) = 33
⎫⎬⎭ This group contains a mistake.
You are correct:
(39)/(33) = 3(9 − 3) = 36, not 33.
Very well, you seem to have a good grasp of the rules for multiplication and division of powers of numbers, stated as follows:
(bm)(bn)
= b(m + n)
(bm)/(bn)
= b(m − n)
Now, let’s go into this matter of exponents a little further. Consider the following division:
(43)/(41) = ?
If you were asked to write the result of this division as a power of 4, what would you write?
(43)/(41) = (64)/(4) = 16
(43)/(41) = 4(3 − 1) = 42
