So, this quarter I started math141 and we're doing review stuff right now, mainly factoring and graphing, things like that.
On a quiz we were told to factor this:
100x^2 - 100
and also:
(2x + 1)x^2 - (2x + 1)9
I factored them the way I was taught to in math 098, but apparently I did it wrong. Now, I completely understood everything in math 098, passed with an A easily so it's not that I just didn't know how to do it.
But, now everything I do is wrong according to this teacher.
So, my question is, how do you factor those two problems?
On a quiz we were told to factor this:
100x^2 - 100
and also:
(2x + 1)x^2 - (2x + 1)9
I factored them the way I was taught to in math 098, but apparently I did it wrong. Now, I completely understood everything in math 098, passed with an A easily so it's not that I just didn't know how to do it.
But, now everything I do is wrong according to this teacher.
So, my question is, how do you factor those two problems?
-
100x^2 - 100
= 100(x^2 - 1)
= 100(x + 1)(x - 1)
(2x + 1)x^2 - (2x + 1)9
= (2x + 1)(x^2 - 9)
= (2x + 1)(x + 3)(x - 3)
= 100(x^2 - 1)
= 100(x + 1)(x - 1)
(2x + 1)x^2 - (2x + 1)9
= (2x + 1)(x^2 - 9)
= (2x + 1)(x + 3)(x - 3)
-
For the first one, you factor out the 100 so that you have:
100 (x^2 - 1)
Then you factor the (x^2 - 1) so that it becomes:
100 (x +1) (x - 1)
For the second one, you factor out the (2x +1) so that you get:
(2x +1) (x^2 - 9)
Then, factor the (x^2 - 9) to get:
(2x +1) (x + 3) (x - 3)
100 (x^2 - 1)
Then you factor the (x^2 - 1) so that it becomes:
100 (x +1) (x - 1)
For the second one, you factor out the (2x +1) so that you get:
(2x +1) (x^2 - 9)
Then, factor the (x^2 - 9) to get:
(2x +1) (x + 3) (x - 3)