a为锐角 cos(a+π/6)=4/5 求sin(2a+π/12)
a为锐角 cos(a+π/6)=4/5 求sin(2a+π/12)
已知a为锐角,且sin a+cos a=根5/2,求sin a*cos a的值
三角函数:设a为锐角,若cos(a+π/6)=4/5,则sin(2a+π/12)的值为多少?
设a为锐角,若cos(a+π/6)=4/5,则sin(2a+π/12)的值为多少?
设a为锐角,若cos(a+π/6)=4/5,则sin(2a+π/12)的值为?
设a为锐角,若cos(a+π/6)=4/5,则sin(2a+π/12)值为
设a为锐角,若cos(a+π/6)=3/5,则sin(a-π/12)=
设A为锐角 若cos(A+π/6)=0.8,则sin(2A+π/12)=?
求正确答案和解析.已知A为锐角,且2tan(π-A)-3cos(π/2+B)+5=0,tan(π+A)+6sin(π+B
若a为锐角,cos(a+30)=4/5,则sin(2a+15)=
已知a是锐角且cos^4a-sin^4a=3/5,求(sin^2a+3sinacosa-cos^2a)/(2sin^2a
已知a为锐角,且sin^2(a)-sinacosa-2cos^2(a)=0 (1)求tana的值 (2)求sin(a-π