Arithmetic Sequence - Write Equation (Formula)

Learn how to work with arithmetic sequences in this free math video tutorial by Mario's Math Tutoring.We discuss how to write a recursive formula and an explicit formula as well as working through some example problems.

0:25 What is a Sequence
1:06 Explicit Formula for Arithmetic Sequences
1:11 Recursive Formula for Arithmetic Sequences
1:28 Example 1 Writing a Recursive Formula for 2,5,8,11,14,...
1:59 What is the Common Difference
3:20 Writing a Formula for 2,5,8,11,14,...
4:25 Example 2 Finding the 10th Term Given the 3rd and 6th Term
5:32 Finding the Slope Between the Two Points
7:05 Using a System of Equations to Find the Formula

Related Videos:

Sum of an Arithmetic Series Formula

Geometric Sequence Formula

Sum of a Finite Geometric Series

Sum of an Infinite Geometric Series

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[carolineholmes]

my teacher is literally not teaching in my class at all and this just made me understand so THANK YOU

[SeanOsborne-sbom]

God bless you, your so good at teaching math... I have a test TODAY and you helped me understand it!

[ShurooqFadhil-lxfp]

This video helped me to better understand the sequence, Thanks!

[tahmenaferdous]

Thank you so much. I figured out the equation for this sequence 3, 7, 11, 15, 19

[sf]

Great lesson. If it was possible, I would give this video more than one like.

[vladimircankov]

Something, i think, worth pointing out (I'm sorry if you mentioned it in some of your other videos. I haven't seen them all yet): how do we tell if some numbers are in an arithmetic sequence?
Lets say numbers "x", "y" and "z". "X" being the smallest and "Z" being the greatest.
If 2y=x+z then the numbers are in an arithmetic sequence. In other words, the middle term is the average of the other two y=(x+z):2

[RGP_]

This guy is carrying my school year on gizmo

[andredelmontdelmont]

Hey, Mario. When you say n=> or = 2, you're talking about n as the internet in question, not the value of that integer, correct?

[federalcat]

I have a midterm today and I'm not going to fail this part because of you thanks!

[SeanOsborne-sbom]

So it doesn't matter which one you use.... if you do them correctly you should get the same thing... right?

[AnushaRamu-nezw]

when you say an-1 do u mean tn = a + (n-1)xd?

[_Sano-]

1, 3, 5, 7…. Find the following terms using a strict arithmetic sequence equation

Strict equation : an = a1 + d(n-1)

a5=
a14=
a78=