Is `7 xx 5 xx 3 xx 2 + 3` a composite number? Justify your answer.

If either vec a = vec 0 or vec a xx vec b = vec 0 .Is the converse true? Justify your answer with an example.

Explain why 7xx11 xx 13 + 13 and 7 xx 6xx 5 xx 4 xx 3 xx 2xx 1 +5 are composite numbers.

Let f be the subset of Z xx Z defined by f={(ab,a+b) : a,b in Z} . Is f a function from Z to Z? Justify your answer.

How will you show that (17xx11xx2)+(17xx11xx5) is a composite number? Explain.

Statement 1: x=1111 91 times of is a composite number. Statement 2: 91 is a composite number.

If n (A) =5 and n(B ) =7 , then the number of relations on A xx B is

If veca=-2hati+3hatj-2hatk, vecb=3hati-hatj+3hatk, vec c=2hati-5hatj+hatk find (veca xx vecb) xx vec c and veca xx (vecb xx vec c) . State whether they are equal.

The sum of the series 1 + 2 xx 3 + 3 xx 5 + 4 xx 7+ ...upto 11th term is