exponents, PLEASE HELP!!?

Question

i don't get how to find this....

(2x - 1)^2

and can u please explain how u got it otherwise I'm stuck lol. Thanks for any help!

Answer 1

Hi,

(2x - 1)^2 really means:

(2x - 1)(2x - 1)

Now distribute the 2x from the first parentheses times both terms in the second parentheses. Then multiply the -1 from the first parentheses times both terms in the second parentheses.

2x(2x - 1) - 1(2x - 1) = 4x^2 - 2x - 2x + 1

Then combine like terms:

4x^2 - 4x + 1


I hope that helps!! :-)

Answer 2

think of this: the number 12. This is a number in decimal notation, and is another way of saying 1*10^1+2*10^0, right?
or 10+2. ok?
so say you have (10+2)^2
(or 12
...x.12...)
how do you solve this?
this is elementary arithmetic, and you should know it, what you might be missing is that this problem is EXACTLY the same thing. The x changes nothing: (10*10+10*2)+(2*10+2*2). Do you follow? this is just how you multiply a 2 digit number. Exactly the same thing in the problem you gave. Consider this and see if it makes the problem easier for you.

Answer 3

Use the binomial theorem, which is pretty useful in this case.
4x^2-4x+1
The binomial theorem states that:
NC0a^n+NC1a^(n-1)b+NC2a^(n-2)b^2...NCNa^0*b^n...
N is the power you are raised to, a is your first number
b is your second number. This works for any power you raise to. on if you are raising an entire binomial to a power.

Answer 4

this is the standard way people square binomials in their head:

(ax + b)^2 = a^2x^2 + 2abx + b^2.

that is, the first one squared, plus 2 times the first times the second,
plus the second one squared.

Answer 5

Write it as (2x - 1)(2x - 1) and use the F.O.I.L. method (First, outside, inside, last) and then combine terms.

Answer 6

(2x - 1)^2=4x^2-4x+1answer

Answer 7

(2x-1)^2
4x^2-4x+1


(a-b)^2=a^2-2ab+b^2

Answer 8

(a-b)^2=a^2-2ab+b^2