7. (i) If A=ф and B={-1, 1} then determine the power set of A×B, B×A and B2 (ii ) If A= {0} and B= {1} then determine the A×B and B×A. Also determine P(A×B) and P(B×A) - Advance Math Class 10 - Exercise: 1.2
(i) Given, A=ф and B={-1, 1}
⇒Now, A×B= ф
B×A= ф
⇒Therefore, P(A×B) ={ ф}
P(B×A)={ ф}
⇒ Again,
= B × B
= {-1, 1} × {-1, 1}
= {(-1, -1), (-1, 1), (1, -1), (1, 1)}
⇒ Therefore,
P( B2)= { ф, {(-1, -1)},{ (-1, 1)}, {(1, -1)}, {(1, 1)}, {(-1, -1), (-1, 1)}, {(-1, -1),(1, -1)}, {(-1, -1), (1, 1)}, {(-1, 1), (1, -1)}, {(-1, 1), (1, 1)}, {(1, -1), (1, 1)}, {(-1, -1), (-1, 1), (1, -1)}, {(-1, -1), (-1, 1), (1, 1)}, {(-1, -1), (1, -1), (1, 1)}, {(-1, 1), (1, -1), (1, 1)}, {(-1, -1), (-1, 1), (1, -1), (1, 1)}}
(ii ) Given, A= {0} and B= {1}
⇒ Therefore, A×B = {(0, 1)}
B×A = {(1, 0)}
⇒ P (A×B) = {ф, {(0, 1)}}
⇒ P (B×A) = {ф, {(1, 0)}}
Exercise: 1.2