grade 8 number theory

Let a=first term, d = common difference, l=t n =last term, s = required sum. Then, Writing the series in the reverse order, Adding together the two series, ..

2, 5, 8, 11, 14 , 32 37, 33 , 1 A sequence is called infinite if the number of terms is infinite. An infinite sequence has no last term. In this sequence, every term is followed by a new ter..

If a:b = 5:8. Find the value of a 2 b+ab 2 :a 3 +b 3..

Let p(x) = 5x 2 +6x-8 Factors of the constant '8' are 1,-1,2,-2,4, -4 and 8,-8. Let us find the value of p(x) at each one of them to get one factor. p(-2) = 20-12-8 = 0 Divide 5x 2 +6x-8 by x+2 to get the other factor. ..

Introduction - You are familiar with factors and products in the case of numbers. For example, 8 is the product of 4 and 2. 4 and 2 are called the products of 8 . Similarly, the algebraic expression a x b x c = abc can be written as 1.a.b.c or 1.ab.c or 1.bc.a or 1.ac...

1. Find the compounded ratio of a) 5:14 and 7:15 b) a+b:a-b; (a 2 -b 2 ):(a 2 +b 2 ) and a 2 +b 2 :(a+b) 2 . 2. In the ratio 7:8, if the consequent is 40, what is the antecedent? 3. Find a) reciprocal ratio of 3:5 b) duplicate ratio of 2:3 c) triplicate ratio of 3:4 d) s..

Let x be added. 380+48x+x 2 =396+40x+x 2 8x=16 x=2 3) Find the fourth proportional to 6, 10 and ..

A square matrix A=[a i j ] n x n is called a diagonal matrix if all the elements, except those in the leading diagonal, are zero. i.e., a i j = 0 for all i ..

a) Ratio of 20 boys to 15 girls. Ratio of boys to girls =4:3 b) Ratio of Rs.50 to Rs.75 c) Ratio of 4m to 160cm..

If m and n are positive integers, and then (i) a m a n = a m + n [Product Law] (ii) [Quotient Law] (iii) (a m ) n = a m n [Power Law]...