8.[判断题]•标准正态分布Phi(x)=int_(-infty)^xvarphi(t)dt=(1)/(sqrt(2pi))int_(-infty)^xe^-(t^(2)/(2))dt,-infty

设X sim N(0,1)，Phi(x) = (1)/(sqrt(2pi)) int_(-infty)^x e^-(t^2)/(2) dt，(x geq 0),

int_(-infty)^+infty delta(t-3)u(t-1), dt 的函数值是 (……)A. 0B. 1C. $\infty$D. 3

(2)int_(-infty)^+infty(dx)/(x^2)+2x+2;(2)$\int_{-\infty}^{+\infty}\frac{dx}{x^{2

(int )_(-infty )^+infty (x)^2(e)^-a(x^2)dx=dfrac (1)(2)sqrt (dfrac {pi )({a)^3}}

当 x > (pi)/(2) 时，int_((pi)/(2))^x ((sin t)/(t)) , dt = ( )A. $\frac{\sin x}{x}$

计算下列各导数：(1) (d)/(dx)int_(0)^x^2sqrt(1+t^2)dt;(2) (d)/(dx)int_(x^2)^x^3(dt)/(sqrt

广义积分int_(1)^+infty(1)/(x^2)dx=（）A. 0B. 1C. -1D. 3

(d)/(dx)int_(sin x)^cos x cos(pi t^2) , dt = ( ). $\frac{d}{dx}\int_{\sin x}^{\c

12、设随机变量X~N(10，0.02²)，已知Phi(x)=int_(-infty)^x(1)/(sqrt(2pi))e^-(u^(2)/(2))du，Phi

(2)已知函数f(x)=int_(0)^sin xsin t^2dt,g(x)=int_(0)^sin xf(t)dt,则A. f(x)是奇函数,g(x)是奇函