设线性无关的函数y1(x)，y2(x)，y3(x)均是方程yˊˊ+p(x)yˊ+q(x)y=f(x)的解C1，C2是任意常数，则该方程的通解是 ( )
A: C1y1+C2y2+y3
B: C1y1+C2y2－(C1+C2)y3
C: C1y1+C2y2－(1－C1－C2)y3
D: C1y1+C2y2+(1－C1－C2)y3
A: C1y1+C2y2+y3
B: C1y1+C2y2－(C1+C2)y3
C: C1y1+C2y2－(1－C1－C2)y3
D: C1y1+C2y2+(1－C1－C2)y3
举一反三
- 方程${{x}^{2}}{{y}^{''}}-(x+2)(x{{y}^{'}}-y)={{x}^{4}}$的通解是( ) A: $y={{C}_{1}}x+{{C}_{2}}{{e}^{x}}-(\frac{1}{2}{{x}^{3}}+{{x}^{2}})$ B: $y={{C}_{1}}x+{{C}_{2}}{{e}^{x}}-(\frac{1}{2}{{x}^{3}}+{{x}^{4}})$ C: $y={{C}_{1}}x+{{C}_{2}}x{{e}^{x}}-(\frac{1}{2}{{x}^{3}}+{{x}^{4}})$ D: $y={{C}_{1}}x+{{C}_{2}}x{{e}^{x}}-(\frac{1}{2}{{x}^{3}}+{{x}^{2}})$
- 下面程序段中正确的是( )。 A: If x＜0 Then y=0 If x＜1 Then y=1 If x＜2 Then y=2 If x＞=2 Then y=3 B: If x＞=2 Then y=3 If x＞1 Then y=2 If x＞=0Then y=1 If x＞0 Then y=0 C: If x＜0 Then y=0 Else If＞=0Then y=1 Else y=3 End If D: If x＞=2 Then y=3 Else If＞=1 Then y=2 Else y=0 End If
- 已知函数由下列方程确定$x^2 - y^2=1 $，则$\frac{d^2 y}{d^2 x} =$( )。 A: $\frac{1}{y^2}$ B: $-\frac{1}{y^2}$ C: $-\frac{1}{y^3}$ D: $\frac{1}{y^3}$
- 设线性无关的函数y1(x)，y2(x)，y3(x)均是方程yˊˊ+p(x)yˊ+q(x)y=f(x)的解C1，C2是任意常数，则该方程的通解是 ( ) A: C1y1+C2y2+y3 B: C1y1+C2y2－(C1+C2)y3 C: C1y1+C2y2－(1－C1－C2)y3 D: C1y1+C2y2+(1－C1－C2)y3
- 已知点()(()-()1(),()y()1())(),()(2(),()y()2())(),()(()-()3(),()y()3())()都在函数()y()=()x()2()的图象上,则()()A.()y()1()<()y()2()<()y()3()B.()y()1()<()y()3()<()y()2()C.()y()3()<()y()2()<()y()1()D.()y()2()<()y()1()<()y()3