If #f(x) = x +5# and #g(x) = 2x + 4#, then what is #(g * f)(2)#?
1 Answer
Oct 24, 2017
Explanation:
#"note "(g*f)(x)=g(x)xxf(x)#
#color(white)(xxxxxxxxxx)=(2x+4)(x+5)#
#"expand factors using the FOIL method"#
#rArr(g*f)(x)=2x^2+14x+20#
#"to obtain "(g*f)(2)" substitute x = 2 into "(g*f)(x)#
#rArr(g*f)(2)=2xx2^2+(14xx2)+20#
#color(white)(xxxxxxxxx)=8+28+20=56#
