Proof Existence and uniqueness of r(t, u)and A(t)follow from Theorem 3. 1. Hence, in order to prove differentiability and the formula for the derivative, it is sufficient to show that there exist a function C: R++R+ such that C(r)/r-0 as r-0 and E>0 such
[填空题] 1.微分方程y+ytanx-cosx=0的通解为y=(x+)cosx 2.过点(,0)且满足关系式yarcsin+y=1的曲线方程为 x 1 yarcsinx=x- C 3.微分方程xy+3y=0的通解为y=C1+2 x 4.设y1(x),y2(x),y3(x)是线性微分方程y\+ax)y+b(x)y=f(x)的三个特解,且 y2(x)-y1(x)+C,则该微分方程的通解为 y3(x)-y(x) y=C1(y2(x)-y1(x))+2((y3(x)-y1(x)+y1(x)。 5.设y1=3+x2,y2=3+x2+e-是某二阶线性非齐次微分方程的两个特解,且相应齐
1:若方程y+p(x)y=0的一个特解为y=cos2x则该方程满足初值条件y(0)=2的 特解为() A cos 2x+2 B cos 2x+1 C2 coS x cos 2X 答案D 解:将y=cos2x代入方程求出函数p(x)再求解方程得到正确答案为D.也可以作 如下分析一阶线性齐次方程 y+p(x)y=0任意两个解只差一个常数因子所以A,B,C三个选项都不是该方程的解 2微分方程“卫