化简2/(cos^2a-sin^2a)
化简Sin A + Sin 2A / 1+cos A +
化简:sin(-a)cos(2π+a)sin(-a-π)
化简sin^2a-cos^2a
化简sin(2π+a)cos(π-a)cos(π/2-a)cos(7π/2-a)/cos(π-a)sin(3π-a)si
【1】化简:sin(a-5π)/cos(3π-a)×cos(π/2-a)/sin(a-3π)×cos(8π-a)/sin
sin^2a+sin^2a.cos^2a+cos^2a化简
化简cos^2(a+15)+sin^2(a-15))+sin(a+180)cos(a-180)
化简[cos(a-π)/sin(π-a)]sin(a-π/2)cos(π/2+a)=
化简~cos^2(a+15)+sin^2(a-15)+sin(a+180)cos(a-180)
化简2/(cos^2a-sin^2a)
化简sin(π+a)cos(-a)+sin(2π-a)cos(π-a)
化简:cos(a-π/2)/sin(5π/2+a)*sin(a-2π)*cos(2π-a)