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:$0.25 per apple
$0.30 per orange
Step-by-step explanation:
I knowwww iM aMbitious and i helped 126
people
Answer:
f(6) = 24
Step-by-step explanation:
f(x) = x^2 - 2x
Let x = 6
f(6) = 6^2 - 2(6)
= 36 - 12
= 24
Answer:
51/60, 52/60
Step-by-step explanation:
20 and 15 are 5×2×2 and 5×3. The smallest common denominator would be 5×2×2×3=60.
Answer:
Option B.
Step-by-step explanation:
Option A.
f(x) = 
Derivative of the given function,
f'(x) = 
= ![(0.5)^x[\text{ln}(0.5)]](https://tex.z-dn.net/?f=%280.5%29%5Ex%5B%5Ctext%7Bln%7D%280.5%29%5D)
= 
Since derivative of the function is negative, the given function is decreasing.
Option B. f(x) = 
f'(x) = 
= ![(5)^x[\text{ln}(5)]](https://tex.z-dn.net/?f=%285%29%5Ex%5B%5Ctext%7Bln%7D%285%29%5D)
= 
Since derivative is positive, given function is increasing.
Option C. f(x) = 
f'(x) = 
= 
= 
Since derivative is negative, given function is decreasing.
Option D. f(x) = 
f'(x) = ![-15^{-x}[\text{ln}(15)]](https://tex.z-dn.net/?f=-15%5E%7B-x%7D%5B%5Ctext%7Bln%7D%2815%29%5D)
= 
Since derivative is negative, given function is decreasing.
Option (B) is the answer.