Where am I going wrong

iCrazzy · 30-10-2018 8:37am #1

I can't seem to find the correct value of x, I've been at this for 30 minutes, I am not sure if my way of doing it is wrong, if someone can please have a look.

Thanks in advance.

Michael Collins · 30-10-2018 1:16pm

Hi iCrazzy,

Why do you subtract the term $gif.download?%285x%5E%7B5n%7D%29%5E0$ on line 4?

iCrazzy · 30-10-2018 2:24pm

Michael Collins wrote: »

Hi iCrazzy,

Why do you subtract the term $gif.download?%285x%5E%7B5n%7D%29%5E0$ on line 4?

Oh crap must be by mistake
So after leaving that out I get 0.94. But that doesn't seem to be right?
Thanks for replying

Michael Collins · 30-10-2018 4:26pm

Your answer of 0.94 is correct (to two decimal places).

The formula for the sum-to-infinity of a geometric series that you used, a/(1-r), assumes a sum from n = 1 to infinity, with 'a' as the first term (x^5 in this case), and 'r' as the common ratio (also x^5 in this case) - I've kept the constant of 5 outside the summation for simplicity.

TheBody · 30-10-2018 4:44pm

Hi op.

Please see attached.

iCrazzy · 01-11-2018 9:10am

Michael Collins wrote: »

Your answer of 0.94 is correct (to two decimal places).

The formula for the sum-to-infinity of a geometric series that you used, a/(1-r), assumes a sum from n = 1 to infinity, with 'a' as the first term (x^5 in this case), and 'r' as the common ratio (also x^5 in this case) - I've kept the constant of 5 outside the summation for simplicity.

Thank you so much for your help

iCrazzy · 01-11-2018 9:11am

TheBody wrote: »

Hi op.

Please see attached.

Thank you for taking the time to do this

Where am I going wrong

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