(1)在Rt△ABC中,∠C=90°,AB=4,BC=3,则sinA=_____,cosA=_____.
问题描述:
(1)在Rt△ABC中,∠C=90°,AB=4,BC=3,则sinA=_____,cosA=_____.
(1)在Rt△ABC中,∠C=90°,AB=4,BC=3,则sinA=_____,cosA=_____.
(2)在Rt△ABC中,∠C=90°,BC=2AC,则sinA=_____,sinB=_____,tanA=_____.
(3)在Rt△ABC中,∠C=90°,且CD⊥AB,CD=4,BD=3,则sinB=_____.
答
(1)sinA=3/4 cosA=(√ 7)/4
(2)sinA=1/2 sinB=(√ 3)/2 tanA=(√ 3)/3
(3)sinB=4/5