What is the exact value of Cosine StartFraction 7 pi Over 12 EndFraction? StartFraction StartRoot 6 EndRoot minus StartRoot 2 EndRoot Over 4 EndFraction StartFraction StartRoot 6 EndRoot + StartRoot 2 EndRoot Over 4 EndFraction StartFraction 2 StartRoot 2 EndRoot minus StartRoot 6 EndRoot Over 4 EndFraction StartFraction StartRoot 2 EndRoot minus StartRoot 6 EndRoot Over 4 EndFraction