求数学学霸解答。
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1)原式=sin(π-π/3)*tan(2π-π/3)
=sinπ/3*(-tanπ/3)
=-sinπ/3*tanπ/3
=-√3/2*√3
=-3/2
2)原式=2cos(180+60)tan(180-60)
=-2cos60*(-tan60)
=cos60*tan60
=cos60*(sin60/cos60)
=sin60
=√3/2
3)原式=sin(4π-π/4)*cos(4π+π/4)+tan(9π-π/4)tan(π+π/4)
=-sinπ/4*cosπ/4+(-tanπ/4)*tanπ/4
=-√2/2*√2/2-1*1
=-1/2-1
=-3/2
4)原式=2[sin(2π+π/4)]^2+[tan(4π+π/4)]^2*tan(π-π/4)
=2(sinπ/4)^2+(tan(π/4)^2*(-tanπ/4)
=2(√2/2)^2+1^2*(-1)
=1-1
=0
=sinπ/3*(-tanπ/3)
=-sinπ/3*tanπ/3
=-√3/2*√3
=-3/2
2)原式=2cos(180+60)tan(180-60)
=-2cos60*(-tan60)
=cos60*tan60
=cos60*(sin60/cos60)
=sin60
=√3/2
3)原式=sin(4π-π/4)*cos(4π+π/4)+tan(9π-π/4)tan(π+π/4)
=-sinπ/4*cosπ/4+(-tanπ/4)*tanπ/4
=-√2/2*√2/2-1*1
=-1/2-1
=-3/2
4)原式=2[sin(2π+π/4)]^2+[tan(4π+π/4)]^2*tan(π-π/4)
=2(sinπ/4)^2+(tan(π/4)^2*(-tanπ/4)
=2(√2/2)^2+1^2*(-1)
=1-1
=0
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