Answer:
the awnser is 250 i took the test and got it correct
Step-by-step explanation:
Answer:
Final answer is c. 15
Step-by-step explanation:
We need to find about what is the first term in the sequence for which d = -2 and a7 = 3
We will use nth term formula of arithmetic sequence.

we have been given a7 that means 7th term is 3
so plug n=7, d=-2 and a_n=3 into above formula




Hence final answer is c. 15
Answer:
Skewed to right
Step-by-step explanation:
there is no explanation, it just is, just like how 1+1 is 2
Brainleist! as you promised!
Proof by induction
Base case:
n=1: 1*2*3=6 is obviously divisible by six.
Assumption: For every n>1 n(n+1)(n+2) is divisible by 6.
For n+1:
(n+1)(n+2)(n+3)=
(n(n+1)(n+2)+3(n+1)(n+2))
We have assumed that n(n+1)(n+2) is divisble by 6.
We now only need to prove that 3(n+1)(n+2) is divisible by 6.
If 3(n+1)(n+2) is divisible by 6, then (n+1)(n+2) must be divisible by 2.
The "cool" part about this proof.
Since n is a natural number greater than 1 we can say the following:
If n is an odd number, then n+1 is even, then n+1 is divisible by 2 thus (n+1)(n+2) is divisible by 2,so we have proved what we wanted.
If n is an even number" then n+2 is even, then n+1 is divisible by 2 thus (n+1)(n+2) is divisible by 2,so we have proved what we wanted.
Therefore by using the method of mathematical induction we proved that for every natural number n, n(n+1)(n+2) is divisible by 6. QED.