-100 - 99 - 98 - ... - 2 - 1 - 0 + 1 + 2 + ... + 97 + 98 + 99. TOLONG DONG DIBACA ,BAGI YG TAU JAWABANNYA PAKE CARA! ( yg jelas )

Mapel : Matematika
Kelas : VII SMP
Materi : Aritmatika dasar

Pembahasan :
Un = 99
a + (n - 1)b = 99
-100 + (n - 1)(-99 + 100) = 99
-100 + (n - 1)1 = 99
-100 + n - 1 = 99
n - 101 = 99
n = 200

-100 - 99 - 98 - ... + 99
= S200
= 200/2(-100 + 99)
= 100(-1)
= -100 ———» Hasil akhir