Question

find the cardinal number of set A = { x : x is a prime number between 5 to 20 }​

Answer 1

Step-by-step explanation:

Number of element in a set is called cardinal number.

(1)A={5,25,125,625}

n(A)=4

(2)B={b,c,d,f,g,h,j,k,l,m,n,p,q,r,s,t,u,v,w,x,y,z}

n(B)=21

(3)X={2,3,5,7,11......}

n(x)=infinite

(4)Q={−3,−2,−1,0,1,2,3,4,5}

n(A)=9