# algebra-expression

May 28th, 2015
Studypool Tutor
Price: \$10 USD

Tutor description

A variable is a symbol that represents a number. Usually we use letters such as n, t, or x for variables. For example, we might say that s stands for the side-length of a square

Word Count: 1457
Showing Page: 1/10
ALGEBRA :1.Sum of first n natural numbers = n(n+1)/22.Sum of the squares of first n natural numbers = n(n+1)(2n+1)/63.Sum of the cubes of first n natural numbers = [n(n+1)/2]24.Sum of first n natural odd numbers = n25.Average = (Sum of items)/Number of itemsArithmetic Progression (A.P.):An A.P. is of the form a, a+d, a+2d, a+3d, ...where a is called the 'first term' and d is called the 'common difference'1.nth term of an A.P. tn = a + (n-1)d2.Sum of the first n terms of an A.P. Sn = n/2[2a+(n-1)d] or Sn = n/2(first term + last term)Geometrical Progression (G.P.):A G.P. is of the form a, ar, ar2, ar3, ...where a is called the 'first term' and r is called the 'common ratio'.1.nth term of a G.P. tn = arn-12.Sum of the first n terms in a G.P. Sn = a|1-rn|/|1-r|Permutations and Combinations :1.nPr = n!/(n-r)!2.nPn = n!3.nP1 = n1.nCr = n!/(r! (n-r)!)2.nC1 = n3.nC0 = 1 = nCn4.nCr = nCn-r5.nCr = nPr/r!Number of diagonals in a geometric figure of n sides = nC2-nTests of Divisibility :1.A number is divisible by 2 if it is an even number.2.A number is divisible by 3 if the sum of the digits is divisible by 3.3.A number is divisible by 4 if the number formed by the last two digits is divisible by 4.4.A number is divisible by 5 if the units digit is either 5 or 0.5.A number is divisible by 6 if the number is divisible by both 2 and 3.6.A number is divisible by 8 if the number formed by the last three digits is divisible by 8.7.A number is divisibl

## Review from student

Studypool Student
" Super fast turn around time. Very impressed and will use Studypool again if I need a quick job. Communication was a bit tough but not unbearable. "

1831 tutors are online

### Other Documents

05/28/2015
05/28/2015
05/28/2015

Brown University

1271 Tutors

California Institute of Technology

2131 Tutors

Carnegie Mellon University

982 Tutors

Columbia University

1256 Tutors

Dartmouth University

2113 Tutors

Emory University

2279 Tutors

Harvard University

599 Tutors

Massachusetts Institute of Technology

2319 Tutors

New York University

1645 Tutors

Notre Dam University

1911 Tutors

Oklahoma University

2122 Tutors

Pennsylvania State University

932 Tutors

Princeton University

1211 Tutors

Stanford University

983 Tutors

University of California

1282 Tutors

Oxford University

123 Tutors

Yale University

2325 Tutors