yego.me
💡 Stop wasting time. Read Youtube instead of watch. Download Chrome Extension

Using explicit formulas of geometric sequences | Mathematics I | High School Math | Khan Academy


less than 1m read
·Nov 11, 2024

The geometric sequence Asobi is defined by the formula, and so they say they tell us that the E term is going to be equal to 3 * -1/4 to the IUS 1 power.

So, given that, what is a sub5, the fifth term in the sequence?

So pause the video and try to figure out what is a subscript 5.

All right, well we can just use this formula. A sub five is going to be every time where I see an I, I replace it with a five.

Is going to be equal to 3 * -1/4 to the 5 - 1 power.

Well, that's equal to 3 * -1/4 to the 4th power.

Well, that's going to be equal to, let's see, we're raising it to an even power, so it's going to give us a positive value.

Since we're going to be multiplying the negative an even number of times, so it's going to be a positive value.

So it's going to be 3 * let's see, 1 to the 1/4 is 1.

The 4th power is just 1, and then 4 to the 4th power, let's see, 4 * 4 is 16.

So 4 * 4 is 4 * 4, so 16 * 16 is 256.

256, and once again, I know it's going to be positive because I'm multiplying a negative times itself four times, or I'm multiplying four negatives together.

So that's going to give me a positive value.

So I get three over 256, and we're done.

That's the fifth term in our sequence: positive 3 over 256.

More Articles

View All
Social consequences of revolutionary ideals | US history | Khan Academy
During the American Revolution, everyone became a little bit of a philosopher. Walking down the street in Boston, past coffee houses and taverns, you might hear ordinary people debating equality and natural rights. Before it was even a political revolutio…
A Belief in Black Magic | Uncensored with Michael Ware
NARRATOR: Finally, the [inaudible] leader agrees to talk. [non-english speech]. He is speaking on behalf of everyone. He says, “Yeah, I’m a pastor. I’m a leader. I’m a Christian. I’m a father. But this belief is part of my life. And I can’t just take it o…
Evidence of evolution: embryology | Evolution | Middle school biology | Khan Academy
Do you ever wish that you had a tail? You could swing your way to school, bake pies more efficiently, and carry an umbrella while keeping your hands free. The funny thing is, you did have a tail once, before you were born. Back then, you were an embryo.…
Aqueous solutions | Solutions, acids, and bases | High school chemistry | Khan Academy
What we have here are drawings of five different glass beakers, each holding different liquids or combinations of liquids and other things. Now, the first one here, I would just call that liquid water. That’s in this beaker. We’re going to assume everyth…
2015 AP Chemistry free response 2a (part 1 of 2) | Chemistry | Khan Academy
Ethine (C₂H₄) molar mass of 28.1 g per mole may be prepared by the dehydration of ethanol (C₂H₅OH) molar mass 46.1 g per mole using a solid catalyst. A setup for the lab synthesis is shown in the diagram above. The equation for the dehydration reaction is…
HAWAII FACTS!
Vsauce! Michael here, and I am back from vacation. You may not have known, but I just spent the last week in Hawaii with my mother and my sister. She’s the one hiding right there. I worked on my tan, grew my beard back out, and most importantly, I learned…