Question

1. If n(A) = 4 then the power set P(A) has how many elements?​

Answer 1

Answer:

Let A={a, b} than the power set is P(A)={ {0}, {a}, {b}, { a,b} } => |P(A)|=4.

Let A={a, b, c} => P(A)= { {0}, {a}, {b}, {c}, {a,b}, {a,c}, {b,c}, {a, b, c} } => |P(A)|=8

And so on.

You can observe, that |P(A)|=2|A| . (You can find a proof everywhere in the internet)

In conclusion: If you have a set of 5 elements, than the power set has 32 elements.