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Square roots 2015-09-21
From mariana:
I have read various articles on how to find the square root of irrational numbers and every article out there seems to be very confusing.
i read you answer to LUKOW about irrational numbers and i am still quite confused. Say i want to find the square root of 326. i know that it is between 18 and 19 because 18 is the square root of 324 and 19 is the square root of 361 im just very confused about the rest of the process. Please help! ( if possible i would appreciate two examples. thanks)

Answered by Penny Nom.
Fractions and square roots 2013-12-04
From arionne:
How do you solve a square root with improper fractions like 121 over 49
Answered by Penny Nom.
Rationals 2009-10-30
From Jawsh:
I don't quite understand the whole idea of rationals. If you have 3Squareroot 49. Is that equal to 3Squareroot 7^2? Can you break it down with an example for me please.
Answered by Robert Dawson.
The square root of a fraction 2008-08-24
From Lauren:
How do you solve square roots of fractions? Does the format change if it is either a proper or an improper fraction?

Ex. the square root of 1/4 or the square roots of 80/25

Answered by Penny Nom.
Simplifying square roots 2007-12-19
From Ciara:
How would you calculate 2 to the square root of 8 plus 4 to the square root of 2 minus 5 to the square root of 2?
Answered by Stephen La Rocque.
1-4/square root 3 2007-09-12
From Prudence:
How to solve this question?
1 - 4/√3

Answered by Penny Nom.
Finding square roots 2007-05-17
From Chandler:
I would like an easy way to find the square root of a number.
Answered by Gabriel Potter.
The square root of 4 2006-05-07
From MaryBeth:
I am a high school teacher of Algebra. I was recently teaching square roots to my students and an interesting question arose. Our textbook seems to be inconsistent. I was hoping you might be able to give our department your opinion on who is correct as we are divided on the correct way to teach this. When you take the square root of a number, you get two answers, a positive root and a negative root, correct? Our book presents this as √4 = 2 and -√4 = -2 and √4 = 2. Shouldn't it be taught as there are always two roots, the positive and the negative? It seems to me, there is really no reason to have to use the as there are always 2 roots, the positive and the negative. But if the negative sign is given then only the negative answer should be given? What's your take?
Answered by Penny Nom.
Finding square roots 2006-04-12
From Fehmida:
I would like to know about tricks or formulas to do complicated square roots. ex. square root of 1029
Answered by Penny Nom and Steve La Rocque.
Square roots 2006-03-07
From Diana:
Find each square root
Answered by Harley Weston.
Square roots and inequalities 2004-10-25
From Waheed:
Q1. What is the simplest way of finding a square root of any number using just a pen and paper? (I am asking this question because I browsed a few sites a didn't find any method that is simpler than the one I use. so I am just curious.)

Q2. Is it possible that you take an equation and turn it into an inequality by performing same mathematical operations on both sides?

Answered by Claude Tardif and Penny Nom.
Double square roots 2002-02-17
From Ali:
i have a question about how to do double square roots with variables and powers.

example : v/"" v/"" 81y8

Answered by Harley Weston.
Squares of negative numbers 2001-11-03
From Susana:
I wanted to know if I can square a negative number..?
Answered by Leeanne Boehm.
The square root of 20 2001-09-18
From Dianna:
How do you simplify a square root? My daughter tells me that the square root of 20 simplified is 5root4
Answered by Penny Nom.
Primes and square roots 2001-06-14
From Paul:
I have a bit of a math problem. It has to do with determining if a very large number is a prime. One method entails dividing the number by every smaller prime number. If any divide into it, it's not a prime. This would be a big job if the number was something like 400 digits long. Another way I read about was to take the square root of the number and test all the primes less than its square root. The explanation went like this: "When a number is divided by another number that is greater than its square root, the result is a number smaller than the square root. For example, the square root of 36 is 6. Dividing 36 by 2, a smaller number than 6, gives 18, a number that is larger than the square root. To prove that 37 is prime it is only necessary to divide it by primes less than 6, since if it had a prime factor greater than 6, it would have to have one less than 6 as well."

I understand the explanation, up to the last sentence. I fail to see the underlying logic. Why if a prime factor exists below the square does one have to exist above the square too? The number 40 can be divided by the prime 2, a number below its square root, but no other primes can do this above its square root. Have I missed something? What's the logic here?

Answered by Claude Tardif and Penny Nom.
Teaching square roots 2001-05-08
From Katie:
My friend and I are doing a project. We have to teach our class about square roots. What is the easiest way to teach square roots to a class?
Answered by Penny Nom.
Finding roots 2001-02-01
From A student:
My math problem is right now we are working on roots. I don't quite understand how to find the answer to the problems, i was wondering what is the easiest, and fastest way to find the answers to roots?
Answered by Penny Nom and Claude Tardif.
Square roots 2000-10-29
From Pamela:

8(Q2) - 5(Q2) + Q2


(1 + Q2)2



Answered by Claude Tardif.
Square roots without a calculator 1999-09-14
From Josh Weiner:
Is there any way to find out a square root without a calculator?
Answered by Harley Weston.
Radicals 1998-09-15
From Lana Sabo:
fifteen times the square root of twenty, divided by the square root of 2.

nine subtract the square root of forty-five, divided by 3.

the square root of 18 plus the square root of 12, divided by the square root of 3.
Answered by Harley Weston.

Square Roots and Functions. 1997-04-23
From Ed:
1. In most texts the solution to a question such as square root x = -6 is

x is undefined.

Yet when teaching to solve
xsquared = 36
x = +6 or -6

There appears to be a contradiction here. My question is when, where and why do we use the principle square root, not both + and -? This often occurs as the extraneous root in the solution of radical equations and in stating the domain and range of functions involving square roots.

2. Are there any simple rules for determining whether equations are functions without graphing them and doing a vertical line test?
Answered by Harley Weston.

Approximating roots. 1996-11-04
From Ben Dixon:
How do you calculate a square root? eg the square root of 2.

There is obviously some sort of successive approximation type algorithm for doing it to however many decimal places is required, but what is the algorithm?
Answered by Harley Weston.

Square roots 1996-03-16
From Terry King and John:
We are just curious about how to manually calculate square roots.
Answered by Harley Weston.
Algorithms for roots 1996-02-22
From Charles Hewitt:
I have seen an algorithm for finding the square root of numbers. Are there similar such algorithms for higher roots?
Answered by Harley Weston.



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