Identify equivalent expressions involving exponents
Key Notes :
๐ Identify Equivalent Expressions Involving Exponents
| ๐น What are Equivalent Exponential Expressions? |
๐ Two expressions are equivalent if they have the same value, even if they look different.
โ Example:
- 23ร22=23+2=25
- So, 23ร22 and 25 are equivalent expressions.
| ๐น Basic Exponent Rules (Laws of Exponents) |
These rules help us find and simplify equivalent exponential expressions:
| Rule Name | Formula | Example |
|---|---|---|
| Product Rule | amรan=am+n | 32ร34=36 |
| Quotient Rule | am/an=amโn | 56/52=54 |
| Power Rule | (am)n=amรn | (23)2=26 |
| Zero Exponent Rule | a0=1(where aโ 0) | 70=1 |
| Negative Exponent Rule | aโn=1/an | 4โ2=1/42=1/16 |
| Power of a Product | (ab)m=amรbm | (2ร3)2=22ร32 |
| Power of a Quotient | (a/b)m=am/bm | (2/5)3=23/53 |
| ๐น How to Identify Equivalent Expressions |
๐ To check if two exponential expressions are equivalent, use these steps:
- Simplify both expressions using exponent rules.
- Compare the base and the exponent.
- If both are the same after simplification โ โ Equivalent!
๐งฎ Example:
- Check if (x2)3 and x6 are equivalent.
- Simplify: (x2)3=x2ร3=x6
- โ Both are equivalent.
| ๐น Common Mistakes to Avoid โ |
โ ๏ธ Donโt add or multiply exponents when bases are different.
- Example: 23+33โ 53 โ
โ ๏ธ Remember that (a+b)nโ an+bn
- Example: (2+3)2=25, but 22+32=13 โ not equal!
| ๐น Real-Life Connection ๐ |
Exponents are used to express:
- Area and volume formulas (e.g., s2, s3)
- Scientific notation (3ร105)
- Growth patterns (population, bacteria growth, etc.)
| โจ Summary |
- Equivalent expressions have the same value.
- Use exponent rules to simplify expressions.
- Always check bases and exponents.
- Avoid common exponent errors.
| ๐ง Example Practice |
- Are 23ร24 and 27 equivalent? โ
- Is (x2)3=x6? โ
- Is 34รท32=32? โ
- Is (2ร3)2=22+32? โ
Learn with an example
Select all the expressions that are equivalent to 85,3-3
- 1/8-9
- 8-9
- 8
- 80
To find which expressions are equivalent to 83.8-3, write each expression with the same base.
The answer choices and 83 . 8 โ3 can all be written as a power of 8. So, use properties of exponents to write each expression in the form 8 ( ). Then, see which ones match 83 . 8 โ3 in this form.
Step 1: Write 83.8โ3 in the form 8( )
83.8โ3
= 83+-3 Use the identity axay = ax+y
= 80
A positive number raised to zeroth power is 1. So, 83 . 8-3 is equal to 1.
Step 2: Now see which expressions are also equal to 80 = 1.
See if 1 / 8-9 is equal to 1.
1 / 8-9
=8-(-9) Use the identity 1/ax=aโx
= 89
So, 1 / 8-9 is equal to 89, but 83 . 8-3 is not. (It is equal to 80=1.)
The expressions1 / 8-9and 83 . 8-3are not equivalent.
The expression 8-9 is in the form 8 . You’ve already found that 83 . 8-3 is not equal to 8-9 (It is equal to 80=1)
The expression 8-9 and 83 . 8-3 are not equivalent.
8 is not equal to 1 , but 83 . 8-3 is equal to 1
The expression 8 and 83 . 8-3 are not equivalent.
you’ve already found 83 . 8-3 is equal to 80 .
The expression 80 and 83 . 8-3 are equivalent.
The correct answer is 80.
Select all the expressions that are equivalent to (103)0.
- 10
- 1/100
- 1
- 1/103
To find which expressions are equivalent to (103)0, write each expression with the same base.
The answer choices and (103)0 can all be written as a power of 10. So, use properties of exponents to write each expression in the form 10 ( )
. Then, see which ones match (103)0 in this form.
Step 1: Write (103)0 in the form 10.
(103)0
= 103.0 Use the identity (ax)y=axy
=100
A positive number raised to zero power is 1. So, (103)0 is equal to 1.
Step 2: Now see which expressions are also equal to 100=1.
10 is not equal to 1, but (103)0 is equal to 1.
The expressions 10 and (103)0 are not equivalent.
See if 1/100 is equal to 1.
1/100
1/1 Use the identity a0=1
1
Both 1/100 and (103)0 are equal to 1.
The expressions 1/100 and (103)0 are equivalent.
You’ve already found that (103)0 is equal to 1.
The expressions 1 and (103)0 are equivalent.
See if 1/103 is equal to 1.
1/103
=10โ3
Use the identity
1/ax=aโx
So, 1/103 is equal to 10โ3, but (103)0 is not. (It is equal to 100=1.)
The expressions 1/103 and (103)0 are not equivalent.
The correct answers are:
=1/100
=1
Let’s practice!

