This week for my blog post, instead of talking about the new lesson we learnt, I chose to discus one of units I reviewed for the mid term… more specifically, a certain way of solving and finding the answer of a certain question that I struggled a lot with while learning this unit.

With the arithmetic and geometric sequences and series, I would always get confused with the questions that give you two different terms (ex. , ) then it asks you to find the difference or the common ratio. I would always wonder how to find the difference/ratio without just guessing so when I was given the change I asked. I found out that knowing the amount of jumps between both of the terms is very important. Before showing the examples, we must clarify that there are 3 terms apart from and .

Arithmetic 

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Geometric 

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So, once you have the difference or ratio, I makes solving the equation so much more easier. For example, once you find the difference or ratio, you can find the first term as well as the nth term formula. Below I included a picture example of a question from the extra practice section, if gives 2 terms of a geometric sequence and asks to find r, 1st terms and nth term formula.