求y=2sin(兀 4-2X)的单调增区间-搜答案-搜搜考试网

y = x^2 sin 4x,求dy,

y'=2xsin4x-x²cos4x·4所以dy=(2xsin4x-4x²cos4x)dxy=ln√4＋t²=1/2ln(4+t²)y'=1/2·1/(4+t&

2kπ-（π/2）

看图片吧

y=sin²2xy′=2×(cos2x)×2sin2x=4cos2x·sin2x=2sin4xy〃=2(4x)′cos4x=8cos4x

y=sin^2x+sinx=(sin^2x+sinx+1/4)-1/4=(sinx+1/2)^2-1/4sinx=-1/2时有最小值-1/4sinx=1时有最大值2

y=sin^2x的周期为π.根据平方正弦公式,y=sin²x=(1/2)(1-cos2x）∵函数cos2x的最小正周期为T=2π/2=π,∴y=sin²x的周期也为T=π

y=sin^x+2sinxcosx=1/2-cos2x/2+sin2x=根号下(5/4)*[2sin2x/根号5-cos2x/根号5]+1/2设cosa=2/根号5,sina=-1/根号5上式=根号下

y'=(cos²x)'-(sin3^x)'=2cosx·(cosx)'-cos3^x·(3^x)'=2cosx·(-sinx)-cos3^x·(3^x·ln3)=-sin2x-ln3·cos

2*cos(x^2)*x/sin(x)^2-2*sin(x^2)*cos(x)/sin(x)^3

sin^2x+cos^2y=1/2∴sin^2x=1/2-cos^2y3sin^2x+sin^2y=3（1/2-cos^2y）+sin^2y=1.5-3cos^2y）+sin^2y又有sin^2y+c

sinx+siny+sinz-sin(x+y+z)=4sin[(x+y)/2]sin[(x+z)/2]sin[(y+z)/2]sinx+siny+sinz-sin(x+y+z)=2sin[(x+y)/

y=sin(x+π/3)sin(x+π/2)=sin(x+π/3)cosx=(sinxcosπ/3+cosxsinπ/3)cosx=1/2sinxcosx+√3/2cos^2(x)[cos^2(x)指

-2k=cos2x-cos2y=[2(cosx)^2-1]-[2(cosy)^2-1]=2[(cosx)^2-(cosy)^2]cos^2x-cos^2y=-k

t=sinx+cosx=√2sin(x+π/4)-√2=再问：上面那个颠倒的V是什么再答：那是根号呀，√2表示根号2.再问：sin^2x这个颠倒的＾也是根号？再答：这个是次方符号呀，sin^2x表示的

配方法y=7/4+sinx-sin^2X=-（sinx-1/2)²+2∵sinx∈[-1,1]∴y∈[-1/4,2]

2x+兀/4=[兀/2+2k兀,3兀/2+2k兀]2x=[兀/4+2k兀,5兀/4+2k兀]x=[兀/8+k兀,5兀/8+k兀]

y'=2e^2xcos(e^2x)把y看成复合函数sint,t=e^m,m=2x.复合函数求导,等于三个分别求导的积

sin(x/2)的周期是4pi,cos2x的周期是pi,sin(x/2)+cos2x的周期是其最小公倍数,自然是4pi

2派比n