(1)sin(-1380°)cos1110°+cos(-1020°)sin750°
=sin(-360°×4+60°)cos(3×360°+30°)+cos(-3×360°+60°)sin(2×360°+30°)
=sin60°cos30°+cos60°sin30°
=sin(60°+30°)
=sin90°
=1;
(2)2sin5π4-cos4π+tan(-π4)
=2sin(π+π4)-cos4π-tanπ4
=-2sinπ4-1-1
=-2-2.
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