jee-main 2020 Q58

jee-main · India · session2_06sep_shift2 Proof Direct Proof of a Stated Identity or Equality
Consider the statement: ``For an integer n, if $\mathrm{n}^{3}-1$ is even, then n is odd''. The contrapositive statement of this statement is:
(1) For an integer n, if n is even, then $\mathrm{n}^{3}-1$ is odd.
(2) For an integer n, if $\mathrm{n}^{3}-1$ is not even, then n is not odd.
(3) For an integer n, if n is even, then $\mathrm{n}^{3}-1$ is even.
(4) For an integer n, if n is odd, then $\mathrm{n}^{3}-1$ is even. 
Consider the statement: ``For an integer n, if $\mathrm{n}^{3}-1$ is even, then n is odd''. The contrapositive statement of this statement is:\\
(1) For an integer n, if n is even, then $\mathrm{n}^{3}-1$ is odd.\\
(2) For an integer n, if $\mathrm{n}^{3}-1$ is not even, then n is not odd.\\
(3) For an integer n, if n is even, then $\mathrm{n}^{3}-1$ is even.\\
(4) For an integer n, if n is odd, then $\mathrm{n}^{3}-1$ is even.
Paper Questions
Q51 Q52 Q53 Q54 Q55 Q56 Q57 Q58 Q59 Q60