Answer:
x=-7
Step-by-step explanation:
-30=5(x+1)
6-1(x+1)
x=-1-6
=-7
Since 68% of the sample ranges from the plus minus first standard deviation from the mean, then interval wherein it will occur will be between 53.5% to 60.5%. I got this answer through adding and subtracting one standard deviation (3.5) from the mean (which is 57).
Answer:
1. x^4 -x^3 -4x^2 -3
a1 = -7.4
an = an-1 -13.8 (choice 1)
Step-by-step explanation:
f(x) = x^4 -x^2 +9
g(x) = x^3 +3x^2 +12
We are subtracting
f(x) -g(x) =x^4 -x^2 +9 - ( x^3 +3x^2 +12)
Distribute the minus sign
x^4 -x^2 +9 - x^3 -3x^2 -12
I like to line them up vertically
x^4 -x^2 +9
- x^3 -3x^2 -12
-------------------------
x^4 -x^3 -4x^2 -3
2. a1 = -7.4
To find the common difference, take term 2 and subtract term 1
-21.2 - (-7.4)
-21.2 + 7.4
-13.8
an = an-1 -13.8
What is the expression though?
The terms of an arithmetic progression, can form consecutive terms of a geometric progression.
- The common ratio is:

- The general term of the GP is:

The nth term of an AP is:

So, the <em>2nd, 6th and 8th terms </em>of the AP are:



The <em>first, second and third terms </em>of the GP would be:



The common ratio (r) is calculated as:

This gives

The nth term of a GP is calculated using:

So, we have:

Read more about arithmetic and geometric progressions at:
brainly.com/question/3927222