How do u do square roots.?

Question

it is confusing

what about the square root of 18.

Answer 1

prime factorisse the no or reduce the expression toirreducible factors.for every pair of the factors pull out one factor to getthesq.rt.
example
1024=2*2*2*2*2*2*2*2*2*2
sq.rt of 1024=2*2*2*2*2=32
sq.rt.of x^4+6x^2+9
x^4+6x^2+9=(x^2+3)^2
=(x^2+3)(x^2+3)
so sq.rt=(x^2+3)

sq.rt.of 18
18=2*3*3
there are 2 factors of 3
you can pull out one
but thereis only one 2
so thesq.rt.is 3rt2

Answer 2

To simplify square roots, all you have to do is know how to:
(1) Take the prime factorization of a number. For instance,

60 = 2 x 2 x 3 x 5
100 = 2 x 2 x 5 x 5

(2) Recognize that (ab)^n = (a^n)(b^n).

As an example, let's say we wanted to reduce sqrt(8).

8 is equal to 2 x 2 x 2, therefore,

sqrt(8) = sqrt[ (2) (2) (2) ]

Now, for EVERY pair numbers which are the same within the square root, cancel the pair out, and write a SINGLE one of what was paired outside the square root.
Thus, the answer is
2sqrt(2)

A second way to look at it:

Remember that the square root of x can also be expressed as x^(1/2). Therefore,

sqrt(8) = 8^(1/2).

Note that we can express 8 as 2 times 4. That is

8^(1/2) = [2 * 4]^(1/2)

If you recall what I said at the beginning of this message, we can individually put an exponent with the 2 and the 4, to make

2^(1/2) * 4^(1/2)

But 4^(1/2) = 2, so we get

2^(1/2) * 2, or
sqrt(2) * 2, or
2 sqrt(2)

Let's try that with your example, sqrt(18).

18 = 3 x 3 x 2

Therefore, sqrt(18) = sqrt(3 x 3 x 2), and we pull both threes out and they come out as one, i.e as

3 sqrt(2)

Answer 3

By definition the every non-negative real number has two square roots; one positive and one negative. The square root of such a real number, is another real number, which when multiplied by itself yields the original real number. For numbers such as 25, 36, or 49, the answers are easy, as these are all perfect squares. So the square roots of these are respectively, positive and negative 5, 6, 7. When a number is not a perfect square (such as in your example), to answer the question, one first needs to know, are you being asked to simplify and give an irrational answer (which itself contains a radical sign) or if one is being asked for the answer as an approximation; e.g., to the nearest tenth. If your question asks for the latter, there are any number of methods (or algorithms) that are available to look for in any elementary algebra book. Of course, if you are just looking for the answer to the nearest 10th you can think, it is more than 4, but less than 5. That is because 4 x 4 = 16 [less than 18] but 5 x 5 = 25 [more than 18]. Then you might try 4.1, 4.2, and 4.3, in each case multiplying the number by itself, and seeing which one is closest to 18. The answer to the nearest 10th would be 4.2. Or you could simply (if permitted) use a calculator. And remember there is both a positive and negative square root, as a positive by a positive as well as a negative times a negative yields a positive result.

Answer 4

well, depending on your teacher, most don't make you find out the exact number. You can just put:
___
V18 put then there are those wacky teachers who make you find th exact number so then just use a calculator =] But if it's something like find the square root of 144. It also means what number multiplied by itself will equal 144. 11x11=121, but that's not 144, 12x12=144, so thus, the square root of 144 is 12.
___
V12

other examples: find the square roots of:

81 (9x9) the square root is 9

64 (8x8) the square root is 8

49 (7x7) the square root is 7

25 (5x5) the square root is 5

Answer 5

say...
5^2=25 the square root of 25 is 5

3^2=9 the square root of 9 is 3

Get it yet?

Answer 6

You find which number you would multiply by itself to get the product. ex. the square root of 49 is 7, because 7x7=49. the square root is 16 is 4 because 4x4=16. it's not that complex of a subject. hope this helps!!

Answer 7

i've only learned about it a little but i think it's when the product is say 144 then the square root would be 12 b/c 12*12 is 144.
ex. square root of 64=8......i think

Answer 8

a sqare root is split dividing evenly. like 4 X 4=16
the square root of 16 is 4. do you see what i am saying?

Answer 9

the easiest way is with a calculator
most numbers do not have an interger as a square root

Answer 10

its just doing wat u did backward
for example 5^2
which equals 25
so then u do it bakwards so itll be 5
4^2=16
sq root is 4
the sq root of 18 is
4.2426