Question

-100-99-98-....-2-1-0+1+2+....+98+99+100=

(Tanpa menghitung satu persatu)

Answer 1

Jumlahkan -100 dg 100, 99 dg -99 dst

maka hasilnua 0

Answer 2

-100 - 99 - 98 - ... + 100 =

U₁ = a = -100
  b = -99 - (-100)
     = 1

Un = a + (n - 1) x b
100 = -100 + (n - 1) x 1
100 = -100 + n - 1
100 = 101 + n
    n = 201

Sn = n/2 x (a + Un)
S₂₀₁ = 201/2 x (-100 + 100)
        = 201/2 x 0
        = 0

semoga jelas dan membantu ya