Question

If f(a) = 3a - a2, which of the following are not true statements?

Select all that apply.
f(4) = -4
f(3) = 0
f(-1) = 2
f(0) = 3
f(-5) = -40

Answer 1

The 3rd and the 4th statement are not the true statements.

Explanation:

In the 3rd statement, if you put a=-1 into the equation f(a), it would be

=3x(-1) - (-1)2

=-3 - 1

=-4.

In the 4th statement, if you put a=0 into the equation f(a), it would be

=3x(0) - (0)2

=0 - 0

=0.

For the other statements, they show the correct results.

Answer 2

f(-1) = 2

f(0) = 3

Explanation:

f(a) = 3a - a²

• f(4)= 3*4-4²= -4 ⇒ correct
• f(3)= 3*3-3²= 0 ⇒ correct
• f(-1) = 3*(-1)-(-1)²=-3+1= -2 ⇒ incorrect
• f(0) = 3*0-0²= 0 ⇒ incorrect
• f(-5) = 3*(-5)-(-5)²= -15-25= -40 ⇒ correct