Ad
related to: which division problem represents the sum of squares of 5 and 3ixl.com has been visited by 100K+ users in the past month
A great way to reinforce learning - Apron Strings & Other Things
- Word Problems
Practice Addition, Geometry, & More
With Relevant Real-World Scenarios.
- Subtraction
Perfect Your Subtraction Skills
With IXL. Start Learning Now!
- Real-Time Diagnostic
Easily Assess What Students Know
& How to Help Each Child Progress.
- IXL K-12 Math Practice
IXL is the Web's Most Adaptive
Math Practice Site. Try it Now!
- Word Problems
Search results
Results from the WOW.Com Content Network
Pierre de Fermat gave a criterion for numbers of the form 8a + 1 and 8a + 3 to be sums of a square plus twice another square, but did not provide a proof. [1] N. Beguelin noticed in 1774 [2] that every positive integer which is neither of the form 8n + 7, nor of the form 4n, is the sum of three squares, but did not provide a satisfactory proof. [3]
[3]: 127 We call a triple (,,) admissible for K if such an identity exists. [1]: 125 Trivial cases of admissible triples include (,,). The problem is uninteresting for K of characteristic 2, since over such fields every sum of squares is a square, and we exclude this case. It is believed that otherwise admissibility is independent of the field ...
In mathematics and statistics, sums of powers occur in a number of contexts: . Sums of squares arise in many contexts. For example, in geometry, the Pythagorean theorem involves the sum of two squares; in number theory, there are Legendre's three-square theorem and Jacobi's four-square theorem; and in statistics, the analysis of variance involves summing the squares of quantities.
This algorithm can easily be adapted to compute the variance of a finite population: simply divide by n instead of n − 1 on the last line.. Because SumSq and (Sum×Sum)/n can be very similar numbers, cancellation can lead to the precision of the result to be much less than the inherent precision of the floating-point arithmetic used to perform the computation.
Legendre's three-square theorem states which numbers can be expressed as the sum of three squares; Jacobi's four-square theorem gives the number of ways that a number can be represented as the sum of four squares. For the number of representations of a positive integer as a sum of squares of k integers, see Sum of squares function.
The sum of squared deviations needed to calculate sample variance (before deciding whether to divide by n or n − 1) is most easily calculated as = From the two derived expectations above the expected value of this sum is
This division sign is also used alone to represent the division operation itself, as for instance as a label on a key of a calculator. The obelus was introduced by Swiss mathematician Johann Rahn in 1659 in Teutsche Algebra. [10]: 211 The ÷ symbol is used to indicate subtraction in some European countries, so its use may be misunderstood. [11]
On the other hand, the primes 3, 7, 11, 19, 23 and 31 are all congruent to 3 modulo 4, and none of them can be expressed as the sum of two squares. This is the easier part of the theorem, and follows immediately from the observation that all squares are congruent to 0 (if number squared is even) or 1 (if number squared is odd) modulo 4.
Ad
related to: which division problem represents the sum of squares of 5 and 3ixl.com has been visited by 100K+ users in the past month
A great way to reinforce learning - Apron Strings & Other Things