(1)sin(-5π/12) (2)cos(-61π/12)

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(1)sin(-5π/12)(2)cos(-61π/12)(1)sin(-5π/12)(2)cos(-61π/12)(1)sin(-5π/12)(2)cos(-61π/12)(1)sin(-5π/12

(1)sin(-5π/12) (2)cos(-61π/12)
(1)sin(-5π/12) (2)cos(-61π/12)

(1)sin(-5π/12) (2)cos(-61π/12)
(1)sin(-5π/12)=-sin(5π/12)=-cosπ/12=-√[(cosπ/6+1)/2]=-√[(√3+2)/4]=-(√6+√2)/4 (2)cos(-61π/12)=cos(-5π-π/12)=-cos(-π/12)=-cosπ/12=-(√6+√2)/4