江画工太猩院 性质26(=A((k为常数为 证6f(x)=m∑6(5)A ′i=1 imk∑(5)x=kim∑f(5)Ax i=1 klf(xdx江西理工大学理学院 ∫ ∫ = ba ba kf(x)dx k f (x)dx (k为常数). 证 ∫ba kf (x)dx i i ni = ∑kf ∆x = →lim ( ) 1 0 ξ λ i i n i = k∑ f ∆x = → lim ( ) 1 0 ξ λ i i n i = k ∑ f ∆x = → lim ( ) 1 0 ξ λ ( ) . ∫ = ba k f x dx 性质2