y=2sin(x+ π /4)cos(x-π /4)和直线在y=1/2在Y轴右侧的交点横坐标从小到大依次记为P1,P2,P3...,则|P2P4|

y=(sin x + COS x)^2 y=2cos x (sin x+cos x) sin(x+y)sin(x-y)=k,求cos^2x-cos^2y 证明COS（X+Y）COS（X-Y）=COS^2X-SIN^2Y 证明cos(x+y)cos(x-y)= cos^2(x)-sin^2(y) y=2cos(x/4+ π/3)-3sin(x- π/4)y=sin(4x- π/3)-cos(3x+π/2) 函数y=cos^4x-sin^4x的最小正周期y=(cos^2x+sin^2x)(cos^2x-sin^2x)为什么等于cos^2x-sin^2x=cos2x谢谢 函数y=sin(x)cos(x+ π/4)+cos(x)sin(x+π/4)的最小正周期是 y=4√2sin x cos x+cos 2x 的值域是 化简y=sin^2(x)+2sin(x)cos(x)+3cos^2(x) 6-4x-x^2=5/|sin(y/x)cos(y/x)|的解 求函数y=7-4sin(x)cos(x)+4cos^2(x)-4cos^4(x)值 求导：y=x-sin(x/2)cos(x/2). 已知sinx=3/5,x∈(π/2,π),求【sin(x+y)+sin(x-y)】/【cos（x+y）+cos（x-y）】的值 y =(cos^2) x - sin (3^x),求y' 求函数y=cos(9/2π+x)+sin^2x的最大值和最小值还有一题 已知sinx+cosx=1/2,求sin^3x+cos^3x和sin^4x+cos^2x Sin x-sin y=2/3 cos x-cos y=1/2 求cos(x-y) y=2sin(x-π/4)cos(x+π/4)+1化简