lessons from the math zone: exponents click to start lesson
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Lessons from the Math Zone: Exponents
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Click to Start Lesson
Mat h ZoneA
= L
x W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h ZoneA
= L
x W
y = mx + b
3x+ 5 = 14
A = pr 2
Lessons fromLessons fromthethe
Math ZoneMath Zone
ExponentsExponents© Copyright 2006, Don Link
Permission Granted for Educational Use Only
1 2 3 4 5
33 33 33 33 33++ ++ ++ ++
33 5××
33 33 33 33 33++ ++ ++ ++
?
33 6××
33++
= 15= 15
= 18= 18
RepeatedRepeated AdditionAddition
Arithmetic ShortcutsArithmetic ShortcutsMat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
1 2 3 4 5
33 33 33 33 33++ ++ ++ ++
33 5××
33 33 33 33 33++ ++ ++ ++
33 6××
33++
1 2 3 4 5
33 33 33 33 33×× ×× ×× ××
33 5^̂
33 33 33 33 33×× ×× ×× ××
?
33 6^̂
33××
= 15= 15
= 18= 18
= 243= 243
= 729= 729
RepeatedRepeated AdditionAddition RepeatedRepeated MultiplicationMultiplication
““caret”caret”
Arithmetic ShortcutsArithmetic Shortcuts
ANALOGYANALOGY
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
33 33 33 33 33×× ×× ×× ××
33 9^̂
33××
= 19,683= 19,683
33 33×× ×× 33××
Another ExampleAnother Example
^
3^919683.
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
33 33 33 33 33×× ×× ×× ××
33 9^̂
33××
= 19,683= 19,683
33 33×× ×× 33××
22 22 22 22 22×× ×× ×× ××
22 9^̂
22××
= 512= 512
22 22×× ×× 22××
Another ExampleAnother ExampleMat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
BaseBase ExponentExponent^̂
33 99^̂
The ExponentExponent tells us how many copies of the BaseBase to multiplymultiply together.
33 99^̂ Multiply 99 copies of 33 together.
Base = 33
Exponent = 99
TerminologyTerminology
(or Power)(or Power)
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Let’s Practice Let’s Practice withwith Calculators Calculators
3^6 = 729= 729
5^6 = 15,625= 15,625
7^7 = 823,543= 823,543
10^4 = 10,000= 10,000
15^7 = 170,859,375= 170,859,375
2^20= 1,048,576= 1,048,576
20^5 = 3,200,000= 3,200,000
1.5^4 = 5.0625= 5.0625
0.2^4 = 0.0016= 0.0016
10.2^4= 10,824.3216= 10,824.3216
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Let’s Practice Let’s Practice withwith Calculators Calculators
3^6 = 729= 729
5^6 = 15,625= 15,625
7^7 = 823,543= 823,543
10^4 = 10,000= 10,000
15^7 = 170,859,375= 170,859,375
2^20= 1,048,576= 1,048,576
20^5 = 3,200,000= 3,200,000
1.5^4 = 5.0625= 5.0625
0.2^4 = 0.0016= 0.0016
10.2^4= 10,824.3216= 10,824.3216
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Good Job!Good Job!
Let’s Practice Let’s Practice withoutwithout Calculators Calculators
3^2 = 9= 9
5^3 = 125= 125
7^3 = 343= 343
10^3 = 1,000= 1,000
15^1 = 15= 15
2^6 = 64= 64
1^9 = 1= 1
0^4 = 0= 0
3^4 = 81= 81
4^3 = 64= 64
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Let’s Practice Let’s Practice withoutwithout Calculators Calculators
3^2 = 9= 9
5^3 = 125= 125
7^3 = 343= 343
10^3 = 1,000= 1,000
15^1 = 15= 15
2^6 = 64= 64
1^9 = 1= 1
0^4 = 0= 0
3^4 = 81= 81
4^3 = 64= 64
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Excellent!Excellent!
FindingFinding the Correct Exponent the Correct Exponent
5×5×5×5×5×5= 5^__= 5^__6611 22 33 44 55 66
8×8×8×8= 8^__= 8^__44
2×2×2×2×2×2×2= 2^__= 2^__77
7×7 = 7^__= 7^__22
1.5×1.5×1.5×1.5×1.5= 1.5^__= 1.5^__55
4×4×4×4× 4×4×4×4× 4×4×4= 4^__= 4^__1111
BaseBase
ExponentExponent
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
FindingFinding the Correct Exponent the Correct Exponent
5×5×5×5×5×5= 5^__= 5^__6611 22 33 44 55 66
8×8×8×8= 8^__= 8^__44
2×2×2×2×2×2×2= 2^__= 2^__77
7×7 = 7^__= 7^__22
1.5×1.5×1.5×1.5×1.5= 1.5^__= 1.5^__55
4×4×4×4×4×4×4×4×4×4×4×4= 4^__= 4^__1313
BaseBase
ExponentExponent
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Cookin’!Cookin’!
933 933 ^̂
““ThreeThree to the ninthninth power”
554 ““FiveFive to the fourthfourth power”
772 ““SevenSeven to the secondsecond power”““or SevenSeven squaredsquared”
10103 ““TenTen to the thirdthird power”““or TenTen cubedcubed”
Exponents Exponents withoutwithout the Caret the Caret
Speaking Math
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
554
Let’s Practice Let’s Practice withwith Calculators Calculators
= 625= 625
94 = 6,561= 6,561
49 = 262,144= 262,144
176 = 24,137,569= 24,137,569
312 = 531,441= 531,441
77 = 823,543= 823,543
0.54 = 0.0625= 0.0625
2.54 = 39.0625= 39.0625
122.52 = 15,006.25= 15,006.25
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
554
Let’s Practice Let’s Practice withwith Calculators Calculators
= 625= 625
94 = 6,561= 6,561
49 = 262,144= 262,144
176 = 24,137,569= 24,137,569
312 = 531,441= 531,441
77 = 823,543= 823,543
0.54 = 0.0625= 0.0625
2.54 = 39.0625= 39.0625
122.52 = 15,006.25= 15,006.25
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Yes Indeed!Yes Indeed!
52
Let’s Practice Let’s Practice withoutwithout Calculators Calculators
= 25= 25
93 = 729= 729
44 = 256= 256
172 = 289= 289
31 = 3= 3
74 = 2,401= 2,401
04 = 0= 0
114 = 1= 1
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
xx1= x 1x = 1
0x = 0
52
Let’s Practice Let’s Practice withoutwithout Calculators Calculators
= 25= 25
93 = 729= 729
44 = 256= 256
172 = 289= 289
31 = 3= 3
74 = 2,401= 2,401
04 = 0= 0
114 = 1= 1
27 = 128= 128
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Right On!Right On!
FindingFinding the Correct Exponent the Correct Exponent
5×5×5×5×5= 5= 5 5511 22 33 44 55
8×8×8×8= 8= 8 44
2×2×2×2×2×2= 2= 2 66
6×6 = 6= 6 22
1.5×1.5×1.5×1.5×1.5= 1.5= 1.5 55
4×4×4×4× 4×4×4×4× 4×4×4×4= 4= 41212
BaseBase
ExponentExponent
??
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
FindingFinding the Correct Exponent the Correct Exponent
5×5×5×5×5= 5= 5 5511 22 33 44 55
8×8×8×8= 8= 8 44
2×2×2×2×2×2= 2= 2 66
6×6 = 6= 6 22
1.5×1.5×1.5×1.5×1.5= 1.5= 1.5 55
4×4×4×4×4×4×4×4×4×4×4= 4= 41212
BaseBase
ExponentExponent
??
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
High Five!High Five!
11
What if the exponent is zero?What if the exponent is zero?
330334 = 81333 = 27332 = 9331 = 3330 =
Let’s Follow a PatternLet’s Follow a Pattern
=–1
–1
÷3
÷3
–1÷3
–1÷3
11
xx0= 1
CLICK for EXTENSION: CLICK for EXTENSION: NegativeNegative Exponents Exponents
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
CLICK for EXTENSION: CLICK for EXTENSION: 0000
?
Name?Name?BaseBase
334
Exponents: Summary and ReviewExponents: Summary and Review
Name?Name?ExponentExponent (or Power)(or Power)
33 99^̂ On calculatorOn calculator
Name?Name?CaretCaret
334= = 33××33××33××33
334“Three to the fourth powerfourth power”
333
332“Three cubedcubed”
“Three squaredsquared”
xx0= 1
xx1= x
The ExponentExponent tells us how many copies of the BaseBase to multiplymultiply together.
Speaking Math
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
For Printing
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Extension: Negative ExponentsExtension: Negative Exponents
332 = 9331 = 3330 = 1
Let’s Extend the PatternLet’s Extend the Pattern
–1 ÷3
–1 ÷3
–1 ÷3
33-1 = 1/3
33-2–1
÷3
= 1/9
=xx -1x1
xx –nxxn1=
=xx -1x1
xx –nxxn1=
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
(-)
5–2
Let’s PracticeLet’s Practice
= 0.04 = 0.04 (1/25)(1/25)
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
With CalculatorsWith Calculators
Use theUse the(-) Key(-) Key
2־ ^50.04
= 0.125 = 0.125 (1/8)(1/8)
5–2
Let’s PracticeLet’s Practice
= 0.04 = 0.04 (1/25)(1/25)
2–3
10–5= 0.00001= 0.00001
0.05–6 = 64,000,000= 64,000,000
3–3= 0.037= 0.037
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
With CalculatorsWith Calculators
037037…037037…
““A A repeating decimalrepeating decimal”
Speaking Math
= 0.125 = 0.125 (1/8)(1/8)
5–2
Let’s PracticeLet’s Practice
= 0.04 = 0.04 (1/25)(1/25)
2–3
10–5= 0.00001= 0.00001
0.05–6 = 64,000,000= 64,000,000
3–3= 0.037= 0.037
1–4 = 1= 1
1 = 1= 1
2–1 = 1/2= 1/2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
With CalculatorsWith Calculators No CalculatorsNo Calculators
037037…037037…
10–5 = 0.00001= 0.00001
4–2 = 1/16= 1/16
10–3 = 1/1000= 1/1000
3–3 = 1/27= 1/27
–12
5–2
Let’s PracticeLet’s Practice
= 0.04 = 0.04 (1/25)(1/25)
2–3 = 0.125 = 0.125 (1/8)(1/8)
10–5= 0.00001= 0.00001
0.05–6 = 64,000,000= 64,000,000
3–3= 0.037= 0.037
1–4 = 1= 1
1–14= 1= 1
2–1 = 1/2= 1/2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
With CalculatorsWith Calculators No CalculatorsNo Calculators
037037…037037…
10–5 = 0.00001= 0.00001
4–2 = 1/16= 1/16
10–3 = 1/1000= 1/1000
3–3 = 1/27= 1/27
Fantastic!Fantastic!Click to RETURN to Main LessonClick to RETURN to Main Lesson
Extension: Zero to the Zero Power?Extension: Zero to the Zero Power?Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
0000
?? What does this mean?What does this mean?
Rule 1: Rule 1: xx00= 1= 1
Rule 2: Rule 2: = 0= 000xx
Anything to the 0 power = 1.Anything to the 0 power = 1.
Zero to any power = 0.Zero to any power = 0.
Which rule should we use?Which rule should we use?
Extension: Zero to the Zero Power?Extension: Zero to the Zero Power?Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
Mat h Zone
A =
L x
W
y = mx + b
3x+ 5 = 14
A = pr 2
0000
?? What does this mean?What does this mean?
When mathematicians have two perfectly When mathematicians have two perfectly good rules that give different answers for good rules that give different answers for
some problem like some problem like 0000, they say the answer , they say the answer is __________ for this case.is __________ for this case.
undefinedundefinedSo, is undefined!So, is undefined!0000
Click to RETURN to Main LessonClick to RETURN to Main Lesson