Discrete Math

Please need help for question 4 and 5

Question 4 Fill in the blanks of the proof of the following statement. Theorem. The sum of two odd numbers is even. Proof. Let n and m be odd numbers. Then n = 2k+1 and m = 26+1 for Then n + m = = 20 Since is an integer, n + m is even. Question 5 Fill in the blanks of the proof of the following statement. Theorem. If n is odd, then 3n' + 4n -5 is even Proof. Let n be odd. Then n =_ for some ke Z. Then 3n' + 4n - 5 = 3(_ ) -5 = 3( - 5 = + = 20 Since is an integer, 3n' + An -5 is even. Question 6 Write a full proof of the following statement. Theorem. The sum of an even number and an odd number is odd