Just need a little clearing up

marlousie

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Jul 19, 2020
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I tried to ask google however it didn't really give me a straight answer so I made an account here solely for this question. It's also relatively simple so thank you to anyone who explains it to me because I'm still a bit caught up on it.

Why does (-4)^2= 16 but -4^2= 1/16

I'm currently studying for the SAT and these things constantly trip me up because my math teachers never really went over this.

Thank you again!
 

Subhotosh Khan

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I tried to ask google however it didn't really give me a straight answer so I made an account here solely for this question. It's also relatively simple so thank you to anyone who explains it to me because I'm still a bit caught up on it.

Why does (-4)^2= 16 but -4^2= 1/16

I'm currently studying for the SAT and these things constantly trip me up because my math teachers never really went over this.

Thank you again!
-4^2= 1/16................................................... is incorrect

-4^2 = - (4^2) = -(16) = -16

However:

4^(-2) = 1/(4^2) = 1/16

Please come back if you have more questions.
 

pka

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I tried to ask google however it didn't really give me a straight answer so I made an account here solely for this question. It's also relatively simple so thank you to anyone who explains it to me because I'm still a bit caught up on it.
Why does (-4)^2= 16 but -4^2= 1/16
I'm currently studying for the SAT and these things constantly trip me up because my math teachers never really went over this.
You are wrong about THAT
\(-4^2=-16\) while \(4^{-2}=\frac{1}{16}\)
 

LCKurtz

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May 3, 2019
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355
I tried to ask google however it didn't really give me a straight answer so I made an account here solely for this question. It's also relatively simple so thank you to anyone who explains it to me because I'm still a bit caught up on it.

Why does (-4)^2= 16 but -4^2= 1/16

I'm currently studying for the SAT and these things constantly trip me up because my math teachers never really went over this.

Thank you again!
It has to do with the precedence of operators. Exponentiation takes precedence over addition and multiplication. So if have \(\displaystyle -4^2\), you would to the exponent first giving \(\displaystyle -16\). Such problems are avoided by using parentheses. \(\displaystyle (-4)^2 = 16\) versus \(\displaystyle -(4^2)=-16\). Then there is no doubt which is meant. On exams like the SAT they give you \(\displaystyle -4^2\) to trip you up if you don't know the precedence rules.
 

marlousie

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Joined
Jul 19, 2020
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4
-4^2= 1/16................................................... is incorrect

-4^2 = - (4^2) = -(16) = -16

However:

4^(-2) = 1/(4^2) = 1/16

Please come back if you have more questions.
Ah, thank you I realize my mistake now! Thank you, I appreciate it :)
 

marlousie

New member
Joined
Jul 19, 2020
Messages
4
You are wrong about THAT
\(-4^2=-16\) while \(4^{-2}=\frac{1}{16}\)
Thank you for the correct way I understand where I went wrong now!
 

marlousie

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Joined
Jul 19, 2020
Messages
4
It has to do with the precedence of operators. Exponentiation takes precedence over addition and multiplication. So if have \(\displaystyle -4^2\), you would to the exponent first giving \(\displaystyle -16\). Such problems are avoided by using parentheses. \(\displaystyle (-4)^2 = 16\) versus \(\displaystyle -(4^2)=-16\). Then there is no doubt which is meant. On exams like the SAT they give you \(\displaystyle -4^2\) to trip you up if you don't know the precedence rules.
Thank you for this! I understand I was wrong in my original post but this explained another problem that I probably would've come across the way! :)
 
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