Answer:
None of these
Step-by-step explanation:

Answer:
+ 1) is an even number.
Take any n ∈ N, then n is either even or odd.
• Suppose n is even ⇒ n = 2m for some m ⇒ n(n + 1) = 2m(n + 1) ⇒ n(n + 1) is even.
• Suppose n is odd ⇒ n+ 1 is even ⇒ n+ 1 = 2m for some m ⇒ n(n+ 1) = 2nm ⇒ n(n+ 1)
is even. QED
2. The sum of the first n natural num
Step-by-step explanation:
a>50A is greater than 50
a<50a<50
a≥50A is greater than or equal to 50
a≤50
Answer:
thanks for the points here u go
Step-by-step explanation:
Answer:
3.5132719e+24
Step-by-step explanation: