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

Question

3185 views around the world

You can reuse this answer
Creative Commons License

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: