高一数学!!!急!!详解!!!

2025-02-24 16:20:20
推荐回答(1个)
回答1:

f(1)=2

2=(a+1)/(b+c)
f(-1)=-f(1)= - 2
-2=(a+1)/(-b+c)
a+1=2(b+c)
a+1= - 2(-b+c)
2b+2c=2b-2c
4c=0
c=0
f(x)=(ax^2+1)/(bx)
f(1)=2
2=(a+1)/b==>a+1=2b
f(2)<3
(4a+1)/(2b)<3
(4a+1)/(a+1)<3
(4a+1)/(a+1)-3<0
(4a+1-3a-3)/(a+1)<0
(a-2)/(a+1)<0
(a-2)(a+1)<0
-1a=2b-1所以,a是奇数;
所以,a=1
b=1
f(x)=(x^2+1)/x
y=(x^2+1)/x
x^2+1=yx
x^2-yx+1=0
因为关于x的方程有解,所以,判别式大于或等于零,
y^2-4≥0
y≥2,或y≤-2
所以原函数的值域为:
(-∞,-2]∪[2,+∞)