设角=-35/6兀,则2sin(兀+a)cos(兀-a)-cos(兀+a)/1+sin^2a+sin(兀-a)-cos^2(兀+a)值=A,/3/3 B.-/3/3 C./3 D.-/3快快点

设角=35/6兀,则2sin(兀+a)cos(兀-a)-cos(兀+a)/1+sin^2a+sin(兀-a)-cos^2(兀+a)值= 设角a=-35π/6,2sin(兀+a)cos(兀-a)-cos(兀+a)/1+sin^2a+sin(兀-a)-cos^2(兀+a)值等于 设角=-35/6兀,则2sin(兀+a)cos(兀-a)-cos(兀+a)/1+sin^2a+sin(兀-a)-cos^2(兀+a)值=A,/3/3 B.-/3/3 C./3 D.-/3快快点 设角A=-35/6π则{2sin(π+a)cos(π-a)-cocs(π+a)}/1+sin^2+sin(π-a)cos^2(π+a)为 设角a=-35π/6,则2sin(π+α)cos(π-α)-cos(π+α)/ 1+sin^2α+sin(π-α)-cos^2(π+α)sina=sin(-35π/6)=sin(-6π+π/6)=1/2 cosα=根号3/22sin(π＋α)cos(π-α)-cos(π+α)/ [1+sin^2α+sin(π-α)-cos^2(π+α)]=2（-sinα)(-cosα）+cosα/[1+sin² 请问数学题,设sin a+cos a=3/5,则sin 2a=? 设角a=-35π/6°,则2sin(π＋α)cos(π-α)-cos(π+α)/1+sin^2α+sin(π-α)-cos^2(π+α) 设α是第二象限角sinα=3/5 求sin(π/6-2a)的值 设a∈(0,兀/2),阝∈(0,兀/2),且tana=1+sin阝/cos阝,则 设a为第一象限角,且sina=3/5,求sin(π+a)+cos(5π-a)/sin(a-6π)+2cos(2π+a) 设a是第三象限角,且sin(a/2)=负根号下1-sin^2(π-a/2),则a/2是第几象限角?有追分 设a是第三象限角,且sin(a/2)=负根号下1-sin^2(π-a/2),则a/2是第几象限角? 设a,B属于[0,兀/2],f（3a+兀/2）=10/13,f（3B+2兀）=6/5 求sin（a 设函数f(x)=sin(2x+∮)(-兀 设△ABC为锐角三角形,a,b,c分别为A,B,C所对的边且sin²A=sin(兀/3+B)sin(兀/3一B)+sin²B.（1）求角A.(2)若AB,AC=12,a=2√7,求b+C. 设A为锐角 若cos(A+π/6)=0.8,则sin(2A+π/12)=? 已知f(x)=2sin(1/3x-兀/6),x属于R,(1)求f(0)的值(2)设a,B属[0,兀/2]...求sin(a+B)已知f(x)=2sin(1/3x-兀/6),x属于R,(1)求f(0)的值(2)设a,B属[0,兀/2],f(3a+兀/2)=10/13,f(3B+兀/2)=6/5求sin(a+B)的值 设sinα=1/2,a为第二象限角,则cos a=?如题