-100-99-98-...-2-1-0+1+2...+48+49+50,,caranya gmna? tolong dijawab ya.. makasih

A = -100
B = -99 - (-100) = 1
Banyak suku :
= 100 + 1 + 50
= 151

S151 :
= n/2 (a + Un)
= 151/2 (-100 + 50)
= 75,5 x -50
= -3775