no e tolong pliss untuk besok

Itu sama seperti bukuku

#3
#a
= (99 + 1) + (97 + 3) + .... 
= 100 + 100 + ...
= 100 x 25
= 2.500

#b
= (1 - 2) + (3 - 4) + ...
= -1 + (-1) + ...
= -1 x 50
= - 50

#c
= -100 - 99 - 98 - ... - 0 + ... + 48 + 49 + 50
= -101 x 50 + 51 x 25
= -5.050 + 1.275
= -3775