一道诱导公式计算题2sin（π+α）cos（π-α

1个回答

2sinα*cosα+cosα分之1+sin方α+sinα-cosα
=cosα（2sinα+1）分之2sin方α+cos方α+sinα-cosα
=cosα（2sinα+1）分之sinα（2sinα+1）+cosα（cosα-1）
=cotα+2sinα+1分之cosα-1
你这道题只能化简到这里

sin(π/2+α)·cos(π/2-α)/cos(π+α)+sin（π-α）·cos（π/2+α）/sin（π+α）=
化简[sin(π/2-α）cos(π/2-α)]/cos(π+α)-[sin(π-α)cos(π/2-α)]/sin(π
化简[sin(π/2+α)*cos(π/2-α)]/cos(π+α)+[sin(π-α)*cos(π/2+α)]/sin
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