Question

Which of the following is not a zero of the function shown below?

f(x)=2x^4-x^3-42x^2+16x+160


a. -4

b. -2

c. 2

d. 4

Answer 1

the answer is 2

Answer 2

2x^4-x^3-42x^2+16x +160

2(2)^4-(2)^3-42(2)^2+16(2) +160

32-8-168+32+160
-112+160=48

Answer 3

put choices into function
when f(x)=0 it must be root of function or zero of function

Answer 4

i understand it now. i didnt get what it was asking before