Question

Confusion! Let f(x)=x^2+5x, g(x)=6-2x, h(x)=2/x-3; find the following value. f(6)-4=

Answer 1

f(6) -4=((6)^2+5(6))-4= 36+30-4= 62

Answer 2

Whoa thanks! Can you please tell me how you got that?

Answer 3

Oh wait, just plug in?

Answer 4

Yeah f(x) is x^2+5x. So f(6) is plugged into the x giving (6)^2+5(6)= 36+30=66. The problem asks for f(6)-4 so that is 66-4=62

Answer 5

Yeah

Answer 6

people don't like to type so they abbreviate with things like f(x)
it means go look for the definition, and replace x with whatever number I put in example f(2) means plug in 2 for x. saves typing.

Answer 7

Oh I see. But I tried this one out: Let f(x)=x^2+5x, g(x)=6-2x, h(x)=2/x-3; find the following value. f(-3). I got -24, is this correct?

Answer 8

9-15= -6

Answer 9

-3*-3 is +9

Answer 10

(-3)^2+5(-3)= 9-15=-6

Answer 11

OH o.k. Now I understand. Thanks guys! :)