问题:单选题微分方程y″-y=ex+1的一个特解应具有形式( )。A aex+bB axex+bC aex+bxD axex+bx...
Thursday, December 1, 2022
问题:若向量X(→)与向量α(→)={2,-1,2}共线,且满足方程α(→)·X(→)=-18,则X(→)=____。...
Thursday, September 22, 2022
问题:设f有二阶偏导数,z=f(xy),则∂2z/∂x∂y等于( )。...
Thursday, September 22, 2022
问题:已知f′(ex)=xe-x,且f(1)=0,则f(x)=____。...
Saturday, September 17, 2022
问题:若物体的运动规律为s=3sin2t,则其在t=0时的速度等于____,加速度为____。...
Thursday, September 22, 2022
问题:设随机变量X服从正态分布N(μ1,σ12),Y服从正态分布N(μ2,σ22),且P{|X-μ1|<1}>P{|Y-μ2|...
Wednesday, September 14, 2022
问题:设a(→),b(→)为非零向量,且a(→)⊥b(→),则必有( )。...
Thursday, September 22, 2022
问题:问答题设f(x)=sinxcosxcos2xcos4xcos8x,求f(n)(0)。...
Thursday, September 21, 2023
问题:已知A为3×4矩阵,X=(x1,x2,x3,x4)T,AX=0有通解k(1,l,O,-1)T,其中k为任意常数,将A中去...
Thursday, September 15, 2022
问题:∫[sec2x/(4+tan2x)]dx=____。...
Wednesday, September 21, 2022
问题:填空题设X、Y相互独立,且E(X)=0,E(Y)=1,D(X)=1,D(Y)=4,则E(X2Y2)=____。...
Monday, December 11, 2023
问题:求出两多项式函数P(x)、Q(x),使得下面等式成立: ∫[(2x4-1)cosx+(8x3-x2-1)sinx]dx...
Thursday, September 22, 2022
问题:设P(A)=0.4,P(B)=0.3,P(A∪B)=0.6,则P(AB(_))=____。...
Thursday, September 22, 2022
问题:设y=y(x)满足∫ydx·∫(1/y)dx=-1,且当x→+∞时y→0,y(0)=1,则y=____。...
Thursday, September 22, 2022
Tuesday, September 20, 2022
问题:设a(→),b(→)为非零向量,且a(→)⊥b(→),则必有( )。...
Thursday, September 22, 2022
问题:已知X~N(μ,σ2),则随σ的增大,P{|X-μ|<σ}( )。...
Thursday, September 22, 2022