Correction to the OA inside the SPOILER:


Confirmation needed please:

Rule 1: (a^b)^c = a^(b*c)

Rule2: a^b^c without any parentheses

We calculate b^c first and then raise it to a^(calculated value of b^c)

The reason I am asking this is because I got a gmat prep question that read:

2^(4-1)^2

I calculated it as 2^6 but the correct answer was

[spoiler]2 ^ 9 [/spoiler]

Feedback appreciated!

I think your rules are correct. But you applied it wrongly.

In this particular question, Your Rule 2 needs to be applied.

2 ^ (4-1)^2
=> 2^3^2

=> 2^9.

cramya wrote:Confirmation needed please:

Rule 1: (a^b)^c = a^(b*c)

Rule2: a^b^c without any parentheses

We calculate b^c first and then raise it to a^(calculated value of b^c)

The reason I am asking this is because I got a gmat prep question that read:

2^(4-1)^2

I calculated it as 2^6 but the correct answer was

[spoiler] 2 ^ 8 [/spoiler]

Feedback appreciated!

Hi ramya
Just as Mani said... ur Rules are right but the application is a bit off..

2^(4-1)^2
= a^(b)^c.. in this case we need to first solve the b^c
= 3^2 = 9
thus its 2^9

had it been
(2^4-1)^2
(2^3)^2 then its (a^b)^c = a^bc
thus its 2^3*2 = 2^6..

hope it makes sense.. do let me know if u need any more clarification the above rule...

Thanks Mani and Sudhir!

just remember BEDMAS---solve whats in Brackets before applying Exponents.

Check this link out. I think these are the only rules you need to know:

https://www.mathwords.com/e/exponent_rules.htm

Let me know.