Question

'For each of the summations given below, use the formula for the sum of the first n integers either to evaluate the sum or to express it in closed form.(a)8+9+10+11+ +700(b)8+9+10+11+ +k

Answer 1

Hi,

Explanation:

a)

`8+9+10+...+700=(693*708)/(2) =245322\\`

b)

`8+9+10+...+k=(((k-8)+1)*(k+8))/(2) =((k-7)*(k+8))/(2)`