InterviewSolution
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Check whether the following statement is true or not:(i) p: If x and y are odd integers, then x + y is an even integer.(ii) q : if x, y are integer such that xy is even, then at least one of x and y is an even integer. |
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Answer» (i) p: If x and y are odd integers, then x + y is an even integer. Let us assume that ‘p’ and ‘q’ be the statements given by p: x and y are odd integers. q: x + y is an even integer the given statement can be written as : if p, then q. Let p be true. Then, x and y are odd integers x = 2m+1, y = 2n+1 for some integers m, n x + y = (2m+1) + (2n+1) x + y = (2m+2n+2) x + y = 2(m+n+1) x + y is an integer q is true. So, p is true and q is true. Hence, “if p, then q “is a true statement.” (ii) q: if x, y are integer such that xy is even, then at least one of x and y is an even integer. Let us assume that p and q be the statements given by p: x and y are integers and xy is an even integer. q: At least one of x and y is even. Let p be true, and then xy is an even integer. So, xy = 2(n + 1) Now, Let x = 2(k + 1) Since, x is an even integer, xy = 2(k + 1). y is also an even integer. Now take x = 2(k + 1) and y = 2(m + 1) xy = 2(k + 1).2(m + 1) = 2.2(k + 1)(m + 1) So, it is also true. Hence, the statement is true. |
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