간편 계산: 986 × 89 - 987 × 88

간편 계산: 986 × 89 - 987 × 88

986 × 89 - 987 × 88 = 986 × 89 - (986 + 1) × 88 = 986 × 89 - 986 × 88 - 88 = 986 - 88 = 898