What is the domain of f(x)?

f(x)= 1/((2x-1)+sqrt(x^2-3)

1 Answer
Dec 31, 2017

D(f)=(-oo,-3]uuu[3,oo)

Explanation:

I_1:(2x−1)+sqrt(x^2−3)!=0
I_2:x^2-3>=0

D(f)=I_1nnnI_2


2x−1+sqrt(x^2−3)!=0

sqrt(x^2−3)!=1-2x

x^2−3!=(1-2x)^2

x^2−3!=1-4x+4x^2

0!=4-4x+3x^2

3x^2-4x+4!=0

"discriminant"<0

=>I_1=RR


x^2-3>=0

(x-3)(x+3)>=0

I_2=(-oo,-3]uuu[3,oo)


D(f)=I_1nnnI_2=RRnnn((-oo,-3]uuu[3,oo))

D(f)=(-oo,-3]uuu[3,oo)