Find the Slowest Growing and the Fastest Growing Functions as X→∞

Multiple Choice

Find the slowest growing and the fastest growing functions as x→∞ .
- $$\begin{array} { l } y = x ^ { 2 } + 7 x \\y = x ^ { 2 } \\y = \sqrt { x ^ { 4 } + x ^ { 2 } } \\y = 2 x ^ { 2 }\end{array}$$

A) Slowest: $y = \sqrt { x ^ { 4 } + x ^ { 2 } }$
Fastest: $y = 2 x ^ { 2 }$
B) Slowest: $y = x ^ { 2 }$ and $y = 2 x ^ { 2 }$ grow at the same rate.
Fastest: $y = \sqrt { x ^ { 4 } + x ^ { 2 } }$
C) Slowest: $y = \sqrt { x ^ { 4 } + x ^ { 2 } }$
Fastest: $y = x ^ { 2 } + 7 x$
D) They all grow at the same rate.