Question

Evaluate f(1) using substitution:
f(x)=2x^3-3x^2-18x+8

Answer 1

@geerky42

Answer 2

could you please help me ?

Answer 3

Plug in 1.

\[f(\color{red}x) = 2\color{red}x^3 - 3\color{red}x^2-18\color{red}x+8\\~\\f(\color{red}1) = 2(\color{red}1)^3-3(\color{red}1)^2-18(\color{red}1)+8\]

Answer 4

i got -11, is that correct?

Answer 5

@geerky42

Answer 6

could you also possibly help me with these two questions too please

Answer 7

-11 ic correct

Answer 8

ok great :)

Answer 9

No idea about 6, but for $5, just plug in 3 for x and 0 for P(x) and check if this equation is true or not.

Make sense?

Answer 10

so on like mathway graphing calculator is should plug 3 in for x and o for P(x)?

Answer 11

Yeah, basically replace x with 3 and P(x) with 0,

then see if equation is true

Answer 12

which one is the P(x)?

Answer 13

the 15(x) or is it something else

Answer 14

3^3-7(3)^2+15(3)-9

Answer 15

or is it something else?

Answer 16

this is what the graph looks like @geerky42