Question

Roller Coaster Crew

Answer 1

Answer:

See explanation below.

Step-by-step explanation:

Part A:

(i). They both correct because they could have a third degree polynomial that crosses the x-axis 3 times.

(ii). To find the zero's of the first one, set function equal to zero and use zero factor principle given as:

$\mathrm{Zero\:Factor\:Principle:\quad \:If}\:ab=0\:\mathrm{then}\:a=0\:\mathrm{or}\:b=0\:\left(\mathrm{or\:both}\:a=0\:\mathrm{and}\:b=0\right)$

So, we have:  

$\mathrm{Solve\:}\:x+2=0:\quad x=-2\\\\\mathrm{Solve\:}\:x-1=0:\quad x=1\\\\\mathrm{Solve\:}\:x-2=0:\quad x=2$