# Thread: Casio fx-100AU PLUS - problem using squared function with negative numbers

1. ## Casio fx-100AU PLUS - problem using squared function with negative numbers

Hello

I am new to doing maths and bought a CASIO fx-100AU PLUS.

Is this a good choice? I am allowed any scientific or graphics calculator for doing calculus.

Also I am confused, when I type in -1 squared it says -1 but -1 times -1 = 1? What am I doing wrong?

Thank you

2. ## Re: Casio fx-100AU PLUS - problem using squared function with negative numbers

I don't have any first hand experience with this calculator but if as you say it says $(-1)^2 = -1$ it is either a complete piece of junk or you are using it wrong somehow.

I kinda suspect the 2nd.

Are you sure you're not keying in $1, (-), (x^2)$ instead of $1, (\pm), (x^2)$ ?

3. ## Re: Casio fx-100AU PLUS - problem using squared function with negative numbers

note that $-1^2 \ne (-1)^2$

$-1^2 = -1 \cdot 1^2 = -1$

$(-1)^2 = (-1)(-1) = 1$