问题
填空题
若tan2a+tana-2=0,则锐角a=______.
答案
tan2a+tana-2=0,
(tana-1)(tan+2)=0,
解得tana=-2(舍去),tana=1.
∴∠A=45°.
故答案为45°.
若tan2a+tana-2=0,则锐角a=______.
tan2a+tana-2=0,
(tana-1)(tan+2)=0,
解得tana=-2(舍去),tana=1.
∴∠A=45°.
故答案为45°.