来自钱红兵的问题
limx趋于π/2(x-π/2)*tanx
limx趋于π/2(x-π/2)*tanx
1回答
2020-12-20 16:10
limx趋于π/2(x-π/2)*tanx
limx趋于π/2(x-π/2)*tanx
令t=x-pi/2,t趋于0,求-t*cost/sint的极限,cost趋于1,t/sint趋于1(洛必达法则),最后答案-1