= 1+cos2(α−β)
曲线f(x)=xlnx在点(1.0)处的切线方程为( )
不能为人体提供能量的营养物质是( )
绿色植物蒸腾作用的意义不包括( )
分布在我国南方地区的热带经济作物是( )
The fans were __________ to know the death of their favourite singer Whitney Huston