# Math Help - math

1. ## math

a^2 - 2a + 1 /2 from a ^2 + 2a - 1 / 2

2. Originally Posted by uma
a^2 - 2a + 1 /2 from a ^2 + 2a - 1 / 2
It would help if you said what is meant to be done with these two expressions.

3. I'm guessing

$a^2-2a+\frac{1}{2} - (a^2+2a-\frac{1}{2})$

You put all the $a^2$s together, all the parts with just $a$ together, and then all numbers with no $a$ together.

So you have
$a^2-a^2$= 0
$-2a - (2a)$ = -4a
$\frac{1}{2} - (-\frac{1}{2})$= 1

altogether giving

$-4a + 1$

4. But he might well mean $\frac{x^2+ 2a+ 1}{2}- \frac{x^2- 2a+ 1}{2}$. That would be $\frac{x^2- x^2+-2a-(=2a)+ 1- 1}{2}$ and I will leave it to the OP to reduce that.