Which of these functions is one-to-one?
A) $f(x)=2 x^{3}-3 x$
B) f(x)=6x +14
C) $f(x)=\sqrt{x^{2}-3 x-2}$
D) $f(x)=5 x^{2}-x+3$
E) $f(x)=\frac{x^{2}+7}{x-1}$

Question

Which of these functions is one-to-one?
A) $f(x)=2 x^{3}-3 x$
B)  f(x)=6x +14 
C) $f(x)=\sqrt{x^{2}-3 x-2}$
D) $f(x)=5 x^{2}-x+3$
E) $f(x)=\frac{x^{2}+7}{x-1}$

Quizplus · Accepted Answer

Function B, $f(x)=6x +14$, is one-to-one because it is a linear function with a non-zero slope, which means it passes the horizontal line test. Linear functions with non-zero slopes are always one-to-one because each x-value maps to exactly one y-value, and each y-value is mapped from exactly one x-value.

Which of These Functions Is One-To-One? A) f(x)=2x3−3xf(x)=2 x^{3}-3 xf(x)=2x3−3x B) F(x)=6x +14 C)

Which of These Functions Is One-To-One?
A) $f(x)=2 x^{3}-3 x$ B) F(x)=6x +14
C)