Question

Let A = {x : x is positive integral multiple of 3 less than 31} and B = { x : x is prime number less than 30}, Then n(AUB) + n(AՈB) is equal to: *

the greatest value of sin x cos x is



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Answer 1

Step-by-step explanation:

S={x:x is a positive multiple of 3 less than 100}

⟹S={3,6,9,12,⋯,99}

⟹n(S)=33

P={x:x is a prime number less than 20}

⟹P={2,3,5,7,11,13,17,19}

⟹n(P)=8

n(S)+n(P)=33+8=41

Answer 2

answer:20

n(AUB)=19

n(AnB)=1

n(AUB)+n(AnB)=20