Class 9th math Review Exercise 3 solution english PCTB

Question # 01: Four option are given against each statement. Encircle the correct option.

\((vii)\)\(\;\)If \(A=\{1,2,3,4\} \) and \(B=\{x,y,z\}\), then cartesian product of \(A\) and \(B\) contains exactly _______ elements.

\( a) \quad \) \(13\)

\( b) \quad \) \(12\)

\(c) \quad \) \(10\)

\( d) \quad \) \(6\)

Answer: \( b) \; \) \( 12\)


Explanation:

Since

\(n(A\times B)=n(A)\times n(B)\)

\(\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ =4\times 3\)

\(\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ =12\)

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