hitunglah B 2+4+6+8+....+200 C 1+3+5+7+......+199 D 1-2+3-4+5-6+.....+200

Mapel : Matematika
Kelas : IX SMP
Bab : Barisan dan deret

Pembahasan :
2 + 4 + 6 + ... + 200 = n² + n
2 + 4 + 6 + ... + 200 = 100² + 100
2 + 4 + 6 + ... + 200 = 10100

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1 + 3 + 5 + ... + 199 = n²
1 + 3 + 5 + ... + 199 = 100²
1 + 3 + 5 + ... + 199 = 10000

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1 - 2 + 3 - 4 + ... + 200
= -1 - 1 - 1 - 1 - ... - 1
= - (1 + 1 + 1 + ...)
= - (200/2)
= - 100