arcsin (x), sin -1 (x), feidhm sine inbhéartach .
Sainmhínítear aircín x mar fheidhm inbhéartach sine x nuair -1≤x≤1.
Nuair a bhíonn sine y cothrom le x:
sin y = x
Ansin tá an t-áirse de x cothrom le feidhm sine inbhéartach x, atá cothrom le y:
arcsin x = sin -1 x = y
arcsin 1 = sin -1 1 = π / 2 rad = 90 °

| Ainm na rialach | Riail | 
|---|---|
| Sín arcsine | sin (arcsin x ) = x | 
| Arcsine de sine | arcsin (sin x ) = x +2 k π, nuair is slánuimhir k ∈ℤ ( k ) | 
| Arcsin argóint dhiúltach | arcsin (- x ) = - arcsin x | 
| Uillinneacha comhlántacha | arcsin x = π / 2 - arccos x = 90 ° - arccos x | 
| Suim Arcsin | arcsin α + arcsin ( β ) = arcsin ( α√ (1- β 2 ) + β√ (1- α 2 ) ) | 
| Difríocht Arcsin | arcsin α - arcsin ( β ) = arcsin ( α√ (1- β 2 ) - β√ (1- α 2 ) ) | 
| Cosine arcsine |  | 
| Tadhlaí arcsine |  | 
| Díorthach arcsine |  | 
| Cuid dhílis éiginnte de arcsine |  | 
| x | arcsin (x) (rad) | arcsin (x) (°) | 
|---|---|---|
| -1 | -π / 2 | -90 ° | 
| -√ 3 /2 | -π / 3 | -60 ° | 
| -√ 2 /2 | -π / 4 | -45 ° | 
| -1/2 | -π / 6 | -30 ° | 
| 0 | 0 | 0 ° | 
| 1/2 | π / 6 | 30 ° | 
| √ 2 /2 | π / 4 | 45 ° | 
| √ 3 /2 | π / 3 | 60 ° | 
| 1 | π / 2 | 90 ° | 
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