Question

given the function:
f(x)=-2x^2-3x+6 Find: f(4)-f(-5)

Answer 1

well,first find f(4)
you can substitute 4 instead of x

Answer 2

but what about the -5?

Answer 3

ok we'll solve it little by little ;)
first find f(4) then i'll tell u what do do ;)

Answer 4

26

Answer 5

oh ok then i find f(5) and subtract right?

Answer 6

i think you've made a mistake ... try it again.

Answer 7

hm

Answer 8

YES! you're very fast to learn :)
then we should subtract them...

Answer 9

-38 forgot the negative

Answer 10

yes,correct and then find f(-5) and then subtract them and give me the final answer :)

Answer 11

-97?

Answer 12

no...try it again what is f(-5) ?

Answer 13

29

Answer 14

-29 not 29 :)

Answer 15

then the result would be -67?

Answer 16

question. what if the f(x) is -x?

Answer 17

@PFEH.1999

Answer 18

-67 ? :|
-38 + 29 = - 67 ????

Answer 19

oh fail

Answer 20

you're very fast and clever but a little careless :)

Answer 21

-9 yea

Answer 22

ok,yes ;)

Answer 23

you said what? you had another question?

Answer 24

yea, small question

Answer 25

what if f(x) was -x

Answer 26

ok,why "what"? we have this function...here's its graph:

Answer 27

so f(-x)=-2x^2-3x+6 is that?

Answer 28

no...f(-x) = -2x^2+3x+6

Answer 29

for x^2 both of them would be same as x^2 = (-x)^2
but for -3x it would be +3x as -3(-x) = 3x
got it?

Answer 30

kind of.. so you are just switching the signs

Answer 31

so it'll end up being -2x^2+3x+6

Answer 32

instead of the -3

Answer 33

yes ;)

Answer 34

any question?

Answer 35

ok,it seems you don't have any question :D ... bye ;)