4×4÷2-(90π×1/360) -(45π×1×2 /360 )=?
4×4÷2-(90π×1/360) -(45π×1×2 /360 )=?
为什么 2π弧度=360度?
已知f(n)=sin[(n+1/2)π+π/4]+cos[(n-1/2)π+π/4]+tan[(n+1)π+π/4].求
函数y=2cos²(x-π÷4)-1是最小正周期为π还是π÷2的奇函数还是偶函数
tan(π/4+a)=1/2 求(sin2a-cos平方a)÷(1+cos2a)
sin2α=sin^2(α+π/4)-cos^2(α+π/4)=2sin^2(a+π/4)-1=1-2cos^2(α+π
1.化简下列各比.36:40 1.2:1 90:360 360:90 1:2.5 2:1/2 3/2 :4/1 0.14
已知f(n)=sin[(n+1\2)π+π\4]+cos[(n-1\2)+π\4]+tan[(n+1)π+π\4],求f
已知sin(π/4+2a)sin(π/4-2a)=1/4,a∈(π/4,π/2)求2sin方a+tana-cota-1
1)tan(x/2+π/4)+tan(x/2-π/4)=2tanx
sin(π+π/6)-cos(π+π/4)cos(-π/2)+1
解方程(1)x-360=312(2)y+2y=45(3)6x-x=125(4)m÷0.6=4.5.