Related Articles
UGC-NET | UGC NET CS 2015 Jun – II | Question 10
• Last Updated : 14 May, 2018

Consider a proposition given as : “ x ≥ 6, if x2 ≥ 5 and its proof as:
If x ≥ 6, then x2 = x.x ≥ 6.6 = 36 ≥ 25
Which of the following is correct w.r.to the given proposition and its proof?
(a)The proof shows the converse of what is to be proved.
(b)The proof starts by assuming what is to be shown.
(c)The proof is correct and there is nothing wrong.

(A) (a) only
(B) (c) only
(C) (a) and (b)
(D) (b) only

Answer: (C)

Explanation: “ x ≥ 6, if x2 ≥ 5 and its proof as:
If x ≥ 6, then x2 = x.x ≥ 6.6 = 36 ≥ 25
it is clear from the above statement that proof starts by assuming what is to be shown and it is clear that the proof shows the converse of what is to be proved hence the proof is not correct.
Statement (a) and (b) are correct but (3) statement is not correct.
So, option (C) is correct.

Quiz of this Question

Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready.

My Personal Notes arrow_drop_up