If the sin 30 degrees is 1/2, then the cos

1 answer:

5 0

Sin 30 degrees = 1 / 2 = opposite / hypotenuse
Adjacent^2 = hyp^2 - opp^2
Adj^2 = 4 - 1
Adj^2 = 3
Adj = sq root (3)
cosine 30 degrees = adjacent / hypotenuse
cosine 30 degrees = sq root (3) / 2
cosine 30 degrees = 1.732 / 2
cosine 30 degrees = .866

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