Let θ be an angle in quadrant 3 such that tanθ=4 over 5 Find the exact values of cosθ and cscθ?
回答 (1)
2016-11-08 5:36 pm
tanθ = 4/5
√(4²+5²) = √41
cosθ = -5/√41
sinθ = -4/√41
cscθ = 1/sinθ = -√41/4
√(4²+5²) = √41
cosθ = -5/√41
sinθ = -4/√41
cscθ = 1/sinθ = -√41/4
收錄日期: 2021-04-22 00:05:38
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