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Which of the following is NOT a zero of the function f(x) = -x^3 + x^2 + 2x?-1 0 2 -2

User Atul Soman
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1 Answer

12 votes
12 votes

Step-by-step explanation

The zeros of a function are all the possible values of x wich makes y=0.

Plugging in -1 into the function:


y=-(-1)^3+(-1)^2+2\cdot(-1)
y=1+1-2

Adding numbers:


y=2-2=0

-1 is a zero of the function.

Let's try with 2:


y(2)=-(2)^3+(2)^2+2(2)
y(2)=-8+4+4
y(2)=0

Applying the same reasoning to x= -2:


y(-2)=_{}-(-2)^3+(-2)^2+2(-2)


y(-2)=8+4-4=12-4=8

In conclusion, the value x=-2 is not a zero of the function.

User Times
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