I have a query regarding one of the exponent properties/rules.
(3^2)^4 = 3^8 => 8 is a result of 2 * 4. This is one of the exponent rules.
How to differentiate between these. How to apply the rule in the below case and which one is right.
(3^2)^(2^2) = (3^2)^4 = 3^8 => The value 8 comes as a result of multiplying 2 and 4.
(3^2)^(2^2) = (3^2)^4 = 3^16 => The value 16 comes as a result of 2 raised to the power of 4.
I am sure only one of these can be right. But I am missing something here. Would be glad if someone could elaborate more on this.
Exponent Rule
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- sam2304
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This is correct.sam2304 wrote:(3^2)^(2^2) = (3^2)^4 = 3^8 => The value 8 comes as a result of multiplying 2 and 4.
This is not.sam2304 wrote:(3^2)^(2^2) = (3^2)^4 = 3^16 => The value 16 comes as a result of 2 raised to the power of 4.
Here is why.
(3^2) = (3*3)
(3^2)^4 = (3^2)*(3^2)*(3^2)*(3^2) = (3*3)*(3*3)*(3*3)*(3*3) = (3*3*3*3*3*3*3*3) = 3^8
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- sam2304
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Let's take another exampleAnurag@Gurome wrote:This is not.sam2304 wrote:(3^2)^(2^2) = (3^2)^4 = 3^16 => The value 16 comes as a result of 2 raised to the power of 4.
Here is why.
(3^2) = (3*3)
(3^2)^4 = (3^2)*(3^2)*(3^2)*(3^2) = (3*3)*(3*3)*(3*3)*(3*3) = (3*3*3*3*3*3*3*3) = 3^8
3^2^2^3 = 3^12 [12 = 2*2*3].
3^2^2^3 = 3^256
What I did in the second case was 3^2^2^3 = 3^2^(8) = 3^(256) and this is wrong because I exponentially raised the value of 2 by 3 and 2 by 8 in the next step instead of multiplying everything. So when it involves power raised to powers, we should just multiply all the powers leaving the base alone and shouldn't raise the powers exponentially, right ?
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Without any brackets, 3^2^2^3 can be interpreted differently.sam2304 wrote:Let's take another example
3^2^2^3
Here are few possibilities,
- 3^2^2^3 = (3^2)^(2^3) = 3^12
3^2^2^3 = (3^((2^2)^3) = 3^64
3^2^2^3 = (3^(2^(2^3)) = 3^256
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what I do in general is - follow the brackets
first solve whatever it is inside any bracket and that the exponent of that number. (Since the exponent rule always confuses me)
If no brackets in exam then you have to go with the way it is written in the exam. if it is a ladder rising up, start solving at the topmost extreme.
Experts?
first solve whatever it is inside any bracket and that the exponent of that number. (Since the exponent rule always confuses me)
If no brackets in exam then you have to go with the way it is written in the exam. if it is a ladder rising up, start solving at the topmost extreme.
Experts?