Question

Can somebody show me how to do this?

Answer 1

Let f(x) = x2 - 3x - 7. Find f(-3).

11

8

-7

-10

Answer 2

Substitute x for -3
\[f(-3) = (-3)^2 - 3(-3) - 7 \]

Answer 3

-3^2 = ?

Answer 4

9

Answer 5

Um... No not exactly... Remember a negative times a positive equals what?

Answer 6

negative

Answer 7

So what would it be?

Answer 8

-9

Answer 9

Good c: Now next you Multiply -3 times -3. A negative times a negative equals what?

Answer 10

so would it be -9 +9 - 7 = -7

Answer 11

Yep c:

Answer 12

You must be very careful with this notation.

\(-3^{2}\)

You will have to be VERY clear if you mean \(-\left(3^{2}\right)\;or\;(-3)^{2}\).

It's not always clear from the context. Various programming languages interpret it differently.

In this case, it is clear from the function notation that we mean \((-3)^{2} = (-3)(-3) = +9\).

Answer 13

It's not "c".

Answer 14

i had it right .-. lol

Answer 15

Sorry :c

Answer 16

Did you know you could use Synthetic Division for that? Pretty cool!

Answer 17

No clue what that is, but thanks.

Answer 18

Im really sorry about tht :/

Answer 19

It's okay. I thought i had lost some of my math skills when you said i wrong though ;D

Answer 20

bahahaha i guess im the one losing my math skills XD

Answer 21

who gets the medal? tk?

Answer 22

or i'll give you medal and you give him medal since you both helped!