-1 - (-7) = 6
5 - (-1) = 6
11 - 5 = 6
The common difference is 6.
If you add 6 to a term, you get the next term.

Looks like your function is

Rewrite it as

Recall that for
, we have

If we replace
with
, we get

By the ratio test, the series converges if

Solving for
gives the interval of convergence,

We can confirm that the interval is open by checking for convergence at the endpoints; we'd find that the resulting series diverge.
You need to type the same equation that’s shown above of the text box. If there’s still a technical issue, let me know, and I’ll try to help!
x = 8
Since x = 8, you can plug in/substitute 8 for "x" in the equation:



2.82842
2.83 You answer is the 4th option
x = 9
Plug in 9 for "x" in the equation



4 Your answer is the 1st option
Answer:
solution given;
let
AB=a
AC=b=30ft
AB=c=20ft
<A=115°
By using Cosine rule.
a²=b²+c²-2bc cos angle
a²=30²+20²-2*30*20 Cos 115°
a²=1807.1419
a=√[1807.1419]
a=42.51
Side A is 42.51ft.
Again
Cos B=
Cos B=
Cos B=0.7687
<B=Cos -¹(0.7687)
<B=39.46°
Angle B is 39.46