Question

5×6×7×11-2×3×7×11 is composite number

Answer 1

5×6×7×11 - 2×3×7×11
= 2310 - 2310
= 0
Thus 0 neither prime nor composite
So the answer is $\fbox{False}$

Answer 2

Let us first understand what is a composite number.

A composite number is a positive integer that has at least one positive divisor other than one or the number itself.

here in this question

7*11*13+13

if you take 13 common you are left with 

 13(7*11+1) 

as you can see the whole number could be easily divided by 13 as that is its factor.

Therefore according to the definition we have at least 3 divisors i.e. 13, the product as in ques(1014)i.e. the number itself and 1.Therefore the number is composite.


same goes with the other example.