3.(2014湖北黄网中考)一Icanhardlybelievemyeyes.IsthatyouLucy?—Yes.Ithasbeenalmost20yearsweweretogether.A.sinceB.beforeC.afterD.until
3. (2014 湖北黄网中考) 一I can hardly believe my eyes. Is that you Lucy?
—Yes.It has been almost 20 years we were together.
A. since B. before C. after D. until
e^y=-(3x+3)*e^(-x)+C如果要以y来重写这项公式,怎么写?y=我自己也有解出y=l 2020-05-13 …
怎样使用matlab解下面的代数方程?急.syms a b c d e;2*b^2=a^2+c^2 2020-05-16 …
求方程xdy+dx=e^ydx的通解移位:dy/(1-e^y)+dx/x=0∫(1+(e^y/(1 2020-06-12 …
y=a^x对x求导,下面有两种求法,1、y=a^x=(e^lna)^x=e^(xlna)所以:y‘ 2020-07-20 …
大学概率论问题,下面这个公式是怎么推导出来的?当X,Y相互独立时,E[(X-E(X))(Y-E(Y 2020-07-25 …
求下列方程的特解y*(1)2y''+y'-y=2e^x(2)y''-3y=x^2+1(3)y''- 2020-07-31 …
求y=2e^x+e^-x的极值//为什么两边取自然对数?由y=2e^x+e^(-x)对y求导:y′ 2020-08-02 …
[ln(x+e^x)]/x=lim(x->0)(1+e^x)/(x+e^x)怎么得到的?原题limx 2020-11-01 …
概率统计问题条件概率与期望:为什么E[(XE(Y|Z))|Z]=E(X|Z)E(Y|Z)?概率统计问 2020-12-01 …
由y+(y^2-1)^2=e^正负(x-1)怎么都得y=0.5×[e的x-1次+e的负(x由y+(y 2021-01-14 …