数学问题(在线等候)!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

来源:百度知道 编辑:UC知道 时间:2024/05/16 08:09:18
f(x)=x^2+lg(x+(x^2+1)^0.5)中,f(a)=M,则f(-a)=?
最快的有加分!!!!!!!!!!!!!!!!!!!!!!!!
答案应该没a的!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

f(x)-x^2=lg(x+(x^2+1)^0.5
-f(-x)+x^2=-lg[x+(x^2+1)^0.5]
=lg1/[x+(x^2+1)^0.5]
=lg(x+(x^2+1)^0.5=f(x)-x^2

f(x)-x^2 为奇函数
f(-a)-a^2=-f(a)+a^2=a^2-M
f(-a)=2a^2-M

有的吧,解法没错啊

f(-x)=(-x)^2+lg(-x+(x^2+1)^0.5)=x^2+lg(1/(x+(x^2+1)^0.5))=x^2-lg(x+(x^2+1)^0.5)
所以f(x)+f(-x)=2x^2,所以f(-x)=2x^2-f(x)
f(-a)=2a^2-f(a)=2a^2-M