C2 help please
Please help me answer this question?
The terms of a geometric series are all positive. The sum of the two terms is 15. The sum to infinity is 27. What are the first two terms of the series.
Well, I tried. I didn't get the right answer and please can you correct it. I started getting confused around the end so just ignore what I did pretty much
.
The terms of a geometric series are all positive. The sum of the two terms is 15. The sum to infinity is 27. What are the first two terms of the series.
Well, I tried. I didn't get the right answer and please can you correct it. I started getting confused around the end so just ignore what I did pretty much
.
(edited 8 years ago)
Your mistake is:
a + a(⅔) = 15
=> a + a = 15/⅔
You haven't divided the first a by ⅔.
a + a(⅔) = 15
=> a + a = 15/⅔
You haven't divided the first a by ⅔.
Original post by Questioness
Please help me answer this question?
The terms of a geometric series are all positive. The sum of the two terms is 15. The sum to infinity is 27. What are the first two terms of the series.
Well, I tried. I didn't get the right answer and please can you correct it. I started getting confused around the end so just ignore what I did pretty much
.
The terms of a geometric series are all positive. The sum of the two terms is 15. The sum to infinity is 27. What are the first two terms of the series.
Well, I tried. I didn't get the right answer and please can you correct it. I started getting confused around the end so just ignore what I did pretty much
.
It was all fine until you correctly got to a + (2/3) * a = 15, but then you divided some of the equation by 2/3 but not all of it so it's lead you to the wrong value of a. Fancy trying again from that point?
Original post by SeanFM
It was all fine until you correctly got to a + (2/3) * a = 15, but then you divided some of the equation by 2/3 but not all of it so it's lead you to the wrong value of a. Fancy trying again from that point?
Original post by TimGB
Your mistake is:
a + a(⅔) = 15
=> a + a = 15/⅔
You haven't divided the first a by ⅔.
a + a(⅔) = 15
=> a + a = 15/⅔
You haven't divided the first a by ⅔.
Yes, makes more sense now. Thank you.
Original post by Questioness
Can someone please explain to me how exactly do you sketch a derivative graph( I think that's what's it's called) as in for example y=5^x. And also how would you know where the graph crosses the axes?
Exponential graph?
Graphs of the form cross the y-axis at and there is an asymptote at . The skew will just be a bit different depending on what a is.
(edited 8 years ago)
Original post by Questioness
Okay thanks
what does your avatar say?
Original post by TeeEm
what does your avatar say?
Dare to be different
Original post by Questioness
Dare to be different
very nice!
Original post by TeeEm
very nice!
Thank ya
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