Question

在Rt△ABC中,∠C=90°,BC=a,AC=b,且3a=4b,则∠A的度数?

Answer 1

∵b=3a/4

tan∠A=a/b

=a/(3a/4)

=4/3.

∠A=arctan(4/3).

∠ A ≈53.13°.