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在△ABC中,∠C=90°,AB=5,BC=4,则cosA的值为( )
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△ABC中∠C=90°AB=8cosA=则BC的长.
在Rt△ABC中∠C=90°AB=3BC=2则cosA的值是.
在Rt△ABC中∠C.=90°BC=1那么AB的长为
sinA
cosA
在ABC中∠C.=90°AC=4BC=3则sinA=cosA.=tgA=.
在△ABC中∠C.=90°AB=13BC=5则cosA的值是
在Rt△ABC中∠C=90°AB=13BC=5求sinAcosAtanA.
在Rt△ABC中∠C.=90°cosA=则∠
的度数是( ) A.30°
45°
60°
90°
如图△ABC中∠B.=90°BC=2AB则cosA=.
在△ABC中∠C=90°BC=3AB=4则下列结论正确的是
sinA=
cosA=
tanA=
cotA=
如图在△ABC中∠C.=90°AB=5BC=3则cosA的值是
在Rt△ABC中∠C.=90°BC=3AC=4那么cosA=.
已知△ABC中AC=4BC=3AB=5则cosA=.
在Rt△ABC中∠C=90°AB=5BC=4则cosA=.
在Rt△ABC中∠ABC=90°AB=3BC=4则sinA=________.
在Rt△ABC中∠C=90°BCAB=13则cosA=.
在Rt△ABC中∠C=90°AB=3BC=2则cosA的值是.
在Rt△ABC中∠C=90°cosA=AB=6则BC=
2
4
6
在Rt△ABC中∠C.=90°BC=3AC=4那么cosA的值等于
在Rt△ABC中∠C.=90°AB=2BC则cosA.的值为.
在△ABC中∠C.=90°AB=5BC=4则tanA.=_________.
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