This is an arithmetic sequence because each term is 7 greater than the previous term, so 7 is what is called the common difference...
Any arithmetic sequence can be expressed as:
a(n)=a+d(n-1), a=first term, d=common difference, n=term number.
We know a=1 and d=7 so:
a(n)=1+7(n-1)
a(n)=1+7n-7
a(n)=7n-6
The above is the "rule" for the nth term.
Answer:
45-n
Step-by-step explanation:
i think this is what you mean
Answer:
You could just replace all the given possible values of k in the inequality and see which ones are solutions, but let's solve this in a more interesting way:
First, remember how the absolute value works:
IxI = x if x ≥ 0
IxI = -x if x ≤ 0
Then if we have something like:
IxI < B
We can rewrite this as
-B < x < B
Now let's answer the question, here we have the inequality:
I-k -2I < 18
Then we can rewrite this as:
-18 < (-k - 2) < 18
Now let's isolate k:
first, we can add 2 in the 3 parts of the inequality:
-18 + 2 < -k - 2 + 2 < 18 + 2
-16 < -k < 20
Now we can multiply all sides by -1, remember that this also changes the direction of the signs, then:
-1*-16 > -1*-k > -1*20
16 > k > -20
Then k can be any value between these two limits.
So the correct options (from the given ones) are:
k = -16
k = -8
k = 0
