Answer: First Option : Sₙ= n/2(a₁ + aₙ)
Step-by-step explanation:
The nth partial sum of an arithmetic sequence or the sum of the first n terms of the arithmetic series can be defined as the sum of a finite number of term in an arithmetic sequence.
It is calculated using the formula:
Sₙ= n/2(a₁ + aₙ)
Where :
a₁ = First term
aₙ = last term
n = number of terms
<u>Answers:</u>
These are the three major and pure mathematical problems that are unsolved when it comes to large numbers.
The Kissing Number Problem: It is a sphere packing problem that includes spheres. Group spheres are packed in space or region has kissing numbers. The kissing numbers are the number of spheres touched by a sphere.
The Unknotting Problem: It the algorithmic recognition of the unknot that can be achieved from a knot. It defined the algorithm that can be used between the unknot and knot representation of a closely looped rope.
The Large Cardinal Project: it says that infinite sets come in different sizes and they are represented with Hebrew letter aleph. Also, these sets are named based on their sizes. Naming starts from small-0 and further, prefixed aleph before them. eg: aleph-zero.
Larissa: y = 250 - 25x
Chucho: y = 30 +30x
4 weeks
Step-by-step explanation: It says it in the problem, and you can see they cross at 4 weeks