(1)函数f(x)=sin(2x+兀/4)+cos(2x+兀/4)在(0,兀/2)单调曾还是减直线对称是 (2)已...(1)函数f(x)=sin(2x+兀/4)+cos(2x+兀/4)在(0,兀/2)单调曾还是减直线对称是 (2)已知Sn是公差不为0的等差数列的前n项和且S1,S2,S3

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(1)函数f(x)=sin(2x+兀/4)+cos(2x+兀/4)在(0,兀/2)单调曾还是减直线对称是 (2)已...(1)函数f(x)=sin(2x+兀/4)+cos(2x+兀/4)在(0,兀/2)单调曾还是减直线对称是 (2)已知Sn是公差不为0的等差数列的前n项和且S1,S2,S3
(1)函数f(x)=sin(2x+兀/4)+cos(2x+兀/4)在(0,兀/2)单调曾还是减直线对称是 (2)已...
(1)函数f(x)=sin(2x+兀/4)+cos(2x+兀/4)在(0,兀/2)单调曾还是减直线对称是 (2)已知Sn是公差不为0的等差数列的前n项和且S1,S2,S3成等比,则(a2+a3)/a1= (3)设F1,F2为双曲线x^2/4+y^2=1的两个焦点,点p在双曲线上满足角F1PF2=90度,则三角形F1PF2的面积是?

(1)函数f(x)=sin(2x+兀/4)+cos(2x+兀/4)在(0,兀/2)单调曾还是减直线对称是 (2)已...(1)函数f(x)=sin(2x+兀/4)+cos(2x+兀/4)在(0,兀/2)单调曾还是减直线对称是 (2)已知Sn是公差不为0的等差数列的前n项和且S1,S2,S3
1.f(x)=-√2cos2x,所以(0,兀/2)单增,对称轴为x=k*(π/2)
2.S1,S2,S3成等比,a1(3a1+3d)=(2a1+d)^2 a1^2+a1d+d^2=0 d/a1=(-1±√5)/2 ,
所以 (a2+a3)/a1=2+3d/a1=(1±√5)/2
3.S=b²÷tan45°=2