#p(x)=3x^2-x^2+2x-5#, what is #p(x)# when #x=-2# and #x=3#?

2 Answers
Mar 29, 2017

#p(-2)=-37" and " p(3)=73#

Explanation:

To evaluate p( -2 ) and p( 3 ) substitute x = - 2 and x = 3
into p( x )

#rArrp(color(red)(-2))=3(color(red)(-2))^3-(color(red)(-2))^2+2(color(red)(-2))-5#

#color(white)(rArrp(-2))=(3xx-8)-(+4)+(2xx-2)-5#

#color(white)(rArrp(-2))=-24-4-4-5#

#color(white)(rArrp(-2))=-37#

#rArrp(color(magenta)(3))=3(color(magenta)(3))^3-(color(magenta)(3))^2+2(color(magenta)(3))-5#

#color(white)(rArrp(3))=(3xx27)-9+6-5#

#color(white)(rArrp(3))=81-9+6-5#

#color(white)(rArrp(3))=73#

Mar 29, 2017

#p(-2)=-37 and p(3)=73#

Explanation:

This is an function, which means that all values of #x# would satisfy the equation.

When #x=-2#,

#p(-2)=3(-2)^3-(-2)^2+2(-2)-5#
#color(white)(xxx//.)=-24-4-4-5#
#color(white)(xxx//.)=-37#

When #x=3#,

#p(3)=3(3)^3-(3)^2+2(3)-5#
#color(white)(x//.)=81-9+6-5#
#color(white)(x//.)=73#