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【单选题】
设f1(χ)和f1(χ)为系数线性齐次微分方程y〞+py′=0的两个特解若由f1(χ)和f1(χ)能构成该方程的通解，下列哪个方程是其充分条件?A.
f1(χ)·f′2(χ)- f2(χ) f′1(χ)=0
B.
f1(χ)·f′2(χ)- f2(χ) f′1(χ)≠0
C.
f1(χ)f′2(χ)+ f2(χ) ·f′1(χ)=0
D.
f1(χ)f′2(χ)+f2(χ) f′1(χ)≠0
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举一反三
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