Question

if ( 3×4×5×7)+(19×21×23) a composite number justify your answer​

Answer 1

Step-by-step explanation:

Hi ,

We know that ,

** prime number :

A natural number greater than 1 is said to be

a prime , if it has only two factors 1 and itself.

***Every composite number has atleast three

factors.

Now ,

According to the problem ,

( 3 × 4 × 5 × 7 ) + ( 19 × 21 × 23 )

= ( 21 × 4 × 5 ) + ( 19 × 21 × 23 )

= 21[ ( 4 × 5 ) + ( 19 × 23 )] { take 21 common ]

= 3 × 7 × k [ where k = (4×5 + 19 × 23 ) = integer ]

= 1 × 3 × 7 × k

= composite numbet ( more than 3 factors )

I hope it helps you.