Let , where is a real parameter. Determine the set of all real values of for which…

MATHEMATICS · Subjective · A Level · Mathematics · Algebra and Functions · Algebra and Functions

Problem

Let

f_k(x)=\sqrt{x^{2}+2kx+9}

, where

k

is a real parameter. Determine the set of all real values of

k

for which the domain of

f_k

\mathbb{R}