How do you evaluate #j(2a)# if #j(x)=1-4x^3#?

2 Answers
Nov 11, 2016

#j(2a)=-32a^3+1#

Explanation:

Plug in #2a# into the equation #j(x)#:

#j(2a) = 1-4(2a)^3#
#=1-4(8a^3)#
#=1-32a^3#

Nov 11, 2016

#j(2a)=1-32a^3#

Explanation:

If #j(color(red)x)=1-4color(red)(x)^3#
then
#color(white)("XXX")j(color(red)(2a))=1-4 * (color(red)(2a))^3#

#color(white)("XXXX")= 1-4 * (8a^3)#

#color(white)("XXXX")=1-32a^3#