First question help. How do i change this to summation series? 49+47+45+.. for 15 terms?

Question

hartnn · Answer

So you need to find the n'th term of that series.
Do you see any pattern in that series ?

anonymous · Answer

-2 :)

hartnn · Answer

good!
thats you common difference
d= - 2

use the general formula for the n'th term of arithmetic sequence
$\large a_n = a_1 +(n-1)d$
a1 = 1st term = 49 here :)

anonymous · Answer

So it would be 49+(n-1)-2?

hartnn · Answer

careful with brackets !

49 + (n-1)(-2)
and yes, simplify this...

anonymous · Answer

so would it be 51-2n?

hartnn · Answer

thats correct!
$\Large \sum \limits_{n=1}^{15}51-2n$

anonymous · Answer

@hartnn thanks so muchh

hartnn · Answer

welcome ^_^
and since you're new here,
$\Huge \mathcal{\text{Welcome To OpenStudy}\ddot\smile} $