Can somebody show m… - QuestionCove
OpenStudy (anonymous):

Can somebody show me how to do this?

3 years ago
OpenStudy (anonymous):

Let f(x) = x2 - 3x - 7. Find f(-3). 11 8 -7 -10

3 years ago
OpenStudy (camerondoherty):

Substitute x for -3 $f(-3) = (-3)^2 - 3(-3) - 7$

3 years ago
OpenStudy (camerondoherty):

-3^2 = ?

3 years ago
OpenStudy (anonymous):

9

3 years ago
OpenStudy (camerondoherty):

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

3 years ago
OpenStudy (anonymous):

negative

3 years ago
OpenStudy (camerondoherty):

So what would it be?

3 years ago
OpenStudy (anonymous):

-9

3 years ago
OpenStudy (camerondoherty):

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

3 years ago
OpenStudy (anonymous):

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

3 years ago
OpenStudy (camerondoherty):

Yep c:

3 years ago
OpenStudy (tkhunny):

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 $$(-3)^{2} = (-3)(-3) = +9$$.

3 years ago
OpenStudy (tkhunny):

|dw:1407768284689:dw|

3 years ago
OpenStudy (tkhunny):

It's not "c".

3 years ago
OpenStudy (anonymous):

i had it right .-. lol

3 years ago
OpenStudy (camerondoherty):

Sorry :c

3 years ago
OpenStudy (tkhunny):

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

3 years ago
OpenStudy (anonymous):

No clue what that is, but thanks.

3 years ago
OpenStudy (camerondoherty):

Im really sorry about tht :/

3 years ago
OpenStudy (anonymous):

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

3 years ago
OpenStudy (camerondoherty):

bahahaha i guess im the one losing my math skills XD

3 years ago
OpenStudy (anonymous):

who gets the medal? tk?

3 years ago
OpenStudy (anonymous):

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

3 years ago