Maths Questions

Use Euclid’s Division Lemma to show that the square of any positive integer is either of the form 3m or 3m + 1 for some integer m.

Solution : By Euclid’s Division Algorithm, we have a = bq + r       …………..(i) On putting b = 3 in (1), we get a = 3q + r,      [0 \(\le\) r < 3] If r = 0   a = 3q  \(\implies\)  \(a^2\) = \(9q^2\)                …

Use Euclid’s Division Lemma to show that the square of any positive integer is either of the form 3m or 3m + 1 for some integer m. Read More »

An army contingent of 616 members is to march behind an army band of 32 members in a parade. The two groups are to march in the same number of columns. What is the maximum number of columns in which they can march ?

Solution : To find the maximum number of columns, we have to find the H.C.F. of 616 and 32 i.e. 616 = 32 \(\times\) 19 + 8 and 32 = 8 \(\times\) 4 + 0 \(\therefore\) H.C.F of 616 and 32 is 8. Hence, maximum number of columns is 8.

Show that any positive odd integer is of the form 6q+1 or 6q+3 or 6q+5, where q is some integer.

Solution : By Euclid’s division algorithm, we have a = bq + r                   ……….(i) On putting, b = 6 in (1), we get a = 6q + r             [0 \(\le\) r < 6] If r = 0, a = 6q, 6q is …

Show that any positive odd integer is of the form 6q+1 or 6q+3 or 6q+5, where q is some integer. Read More »

Use Euclid’s division algorithm to find the H.C.F of :

Question : Use Euclid’s division algorithm to find the H.C.F of : (i) 135 and 225 (ii) 196 and 38220 (iii) 865 and 225 Solution : (i) We start with the larger number 225. By Euclid’s Division Algorithm, we have 225 = 135 \(\times\) 1 + 90 We apply Euclid’s Division Algorithm on Division 135 …

Use Euclid’s division algorithm to find the H.C.F of : Read More »

What are Universal Relation with Example ?

Solution : Let A be a set. Then, A \(\times\) A \(\subseteq\) A \(\times\) A and so it is a relation on A. This relation is called the universal relation on A. In other words, a relation R on a set is called universal relation, if each element of A is related to every element …

What are Universal Relation with Example ? Read More »

Prove that the total number of subsets of a finite set containing n elements is \(2^n\).

Solution : Let A be a finite set containing n elements. Let 0 \(\le\) r \(\le\) n. Consider those subsets of A that have r elements each. We know that the number of ways in which r elements can be chosen out of n elements is \(^nC_r\). Therefore, the number of subsets of A having …

Prove that the total number of subsets of a finite set containing n elements is \(2^n\). Read More »

Ezoicreport this ad