Explain why (17 x

17 × 5 × 11 × 3 × 2 + 2 × 11 ..... (i)

= 2 × 11 × (17 × 5 × 3 + 1)

= 2 × 11 × (255 + 1) −2 × 11 × 256

Number (i) is divisible by 2, 11 and 256, it has more than 2 prime factors.

Therefore (17 × 5 × 11 × 3 × 2 + 2 × 11) is a composite number.