sin(X*2 y*2)除以(x*2 y*2)的极限

x^2=x的平方‘/’为除以[(x+2y)^2-(x+y)(x-y)-5y^2]/(2x)=[(x^2+4xy+4y^2)-(x^2-y^2)-5y^2]/(2x)=[4xy]/(2x)=2y[(3x

注意ρ代表积分变量而R是积分限,所以在ρ的积分表达式中应该是关于ρ表达式而不是关于R的,所以最后一个ρ的积分应该是∫(sinρ/ρ)ρ^2dρ,积分限都是正确的.所以应该是∫dθ∫sinφdφ∫ρsi

2X-Y/X+Y=2X+Y/2X-Y=1/2原式＝[2(2X-Y)/X+Y]-[4(X+Y)/2X-Y]=2*2-4*(1/2)=4-2=2P.S.第一次为团队答题,好鸡东哦o(∩_∩)o有什么不懂的

x=0:0.01:1;y=0;fori=1:20y=y+sin(i*x);endplot(y);

y=(2x+3)/(x-1)=[2(x-1)+2+3]/(x-1)=2+5/(x-1)x＜1,∴5/(x-1)＜0,∴y＜2或∵x＜1,x-1≠0,变换得y(x-1)=2x+3,即x=(3+y)/(y

(x-y)(z+y-x+y+2y)÷4y=(x-y)(z-x+4y)÷4y{(x+y)(x-y)-(x-y)的2次方+2y(x-y)}除以4y=(x-y)(x+y-x+y+2y)÷4y=(x-y)(4

tan,正切；sin,正弦；cos,余弦tan(x+y)tan(x-y)=sin(x+y)/cos(x+y)*sin(x-y)/cos(x-y)=sin(x+y)sin(x-y)/[cos(x+y)c

Y=（sin^4x+cos^4x+sin^2xcos^2x）/（2-sin2x）=（(sin^2x+cos^2x)^2-sin^2xcos^2x)/（2-sin2x）=(1-sinxcosx)(1+s

【(x-y)^2+(x+y)(x-y)】除以2x=(x-y)*(x-y+x+y)/2x=(x-y)*2x/2x=x-y

左边=(sinxcosy+cosxsiny)(sinxcosy-cosxsiny)=sin²xcos²y-cos²xsin²y=sin²x(1-sin

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

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)/

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

对这样的隐函数求导数的时候,就把y看作x的函数,y对x求导就得到dy/dx所以原等式对x求导得到2xy²+x²*2y*dy/dx+siny+x*cosy*dy/dx=0于是化简得到

y=√7/2[sinx*√21/7-cosx*2√7/7)令cosθ=√21/7,sinθ=2√7/7),y=√7/2sin(x-θ),值域：y∈[-√7/2,√7/2].

y=sin²x+2sinxcosx+3cos²xy=(sin²x+cos²x)+2sinxcosx+(2cos²x-1)+1=1+sin2x+cos2

∵-1≤cosx≤1,所以2-cosx恒≥1∴原式可化为√3sinx=2Y-cosxY===>√3sinx+cosxY=2Y三角代换：sin(x+a)=2Y/√(3+y²)∴-1≤2Y/√(

[(x²-y²)²/(x+y)²]/(x-y)=[(x+y)(x-y)/(x+y)]²/(x-y)=(x-y)²/(x-y)=x-y如果不懂

我来给你解答,稍等再答：

f(x)={sin(-x)/x,x