4! + 5! – 3!!___________sepi ya_.
4! + 5! – 3!!
_____
( 4 × 3 × 2 × 1 ) + ( 5 × 4 × 3 × 2 × 1 ) – ( 3 × 1 )
= ( 12 × 2 × 1 ) + ( 20 × 3 × 2 × 1 ) – 3
= ( 24 × 1 ) + ( 60 × 2 × 1 ) – 3
= 24 + ( 120 × 1 ) – 3
= 24 + 120 – 3
= 144 – 3
= 141.
→ 4! + 5! – 3!!
→ (4 × 3 × 2 × 1) + (5 × 4 × 3 × 2 × 1) – (3 × 1)
→ 24 + 60 – 3
→ 84 – 3
→ 81