Answer:
x=-2 x=2 x = 1/2 x=3
Step-by-step explanation:
f(x) = 2x^4 − 5x^3 − 5x^2 + 20x − 12
Graph
We see that there is a zero at -2
Using synthetic division
-2 2 -5 -5 20 -12
-4 18 -26 12
------------------------------
2 -9 13 -6 0
This gives us ( x+2) ( 2x^3 -9x^2 +13x -6)
We see that there is a zero at 2
Using synthetic division ( 2x^3 -9x^2 +13x -6)
2 2 -9 13 -6
4 -10 6
------------------------------
2 -5 3 0
This gives us ( x+2) ( x-2) ( 2x^2 -5x+3)
We can factor ( 2x^2 -5x+3)
( x+2) ( x-2) ( 2x -1) ( x-3)
Using the zero product property
( x+2)=0 ( x-2)=0 ( 2x -1)=0 ( x-3)=0
x=-2 x=2 x = 1/2 x=3
