已知函数f(x)=1+x-(x^2)/2+(x^3)/3-(x^4)/4+……+(x^2011)/2011,g(x)=1-x+(x^2)/2-(x^3)/3+(x^4)/4-……-(x^2011)/2011,设F(x)=f(x+3)*g(x-3),qie函数F(x)的零点均在区间【a,b】(a
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已知函数f(x)=1+x-(x^2)/2+(x^3)/3-(x^4)/4+……+(x^2011)/2011,g(x)=1-x+(x^2)/2-(x^3)/3+(x^4)/4-……-(x^2011)/2011,设F(x)=f(x+3)*g(x-3),qie函数F(x)的零点均在区间【a,b】(a
答
答案是1吗?是我给你写步骤
答
两式相加,我们容易得到:f(x)+g(x)=2对于f(x),求导,我们有:f'(x)=1-x+x^2-x^3.+x^2010当x=-1时,f'(-1)=2011当x≠-1时,f'(x)=(1-(-x)^2011)/(1-(-x))=(1+x^2011)/(1+x)x>-1时 f'(x)>0,单调增x0,所以 f(x)是单调增函...