If $f(x) = 2x^2 - 3x + 2$ , what is $f(-2/3)$ ?

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Answer 1 · 2018-03-20T02:18:04

$44/9 or 4 8/9 or 4.88889$ Because $f(x)=2x^2-3x+2$ , and $f(-2/3)$ , this means $-2/3$ should be inserted for $x$ .

$(-2/3)^2=(-2/3)*(-2/3)=4/9$
$4/9*2=8/9$
$-3*(-2/3)=(-2*-3)/3=6/3=2$
$2+2+8/9=4 8/9= 4.88889$

Answer 2 · 2018-03-20T02:20:41

$f(-2/3)=44/9$

Simply plug in $-2/3$ for $x$ into $f(x)$ :

$color(white)=f(-2/3)$

$=2(-2/3)^2-3(-2/3)+2$

$=2((-2)^2/3^2)-3(-2/3)+2$

$=2(4/9)-3(-2/3)+2$

$=(2*4)/9-3(-2/3)+2$

$=8/9-3(-2/3)+2$

$=8/9+3(2/3)+2$

$=8/9+color(red)cancelcolor(black)3(2/color(red)cancelcolor(black)3)+2$

$=8/9+2+2$

$=8/9+4$

$=8/9+36/9$

$=(8+36)/9$

$=44/9~~4.888889$

We can use a calculator to check our work:

![https://www.desmos.com/calculator]( useruploads.socratic.org )

If f(x) = 2x^2 - 3x + 2f(x) = 2x^2 - 3x + 2, what is f(-2/3)f(-2/3)?