How do you find #(goh)(1)# given #g(x)=x^2+4+2x# and #h(x)=-3x+2#?
1 Answer
Feb 17, 2017
Explanation:
Find (g○h)(x) = g(h(x)) to begin with.
#g(h(x))=g(color(red)(-3x+2))#
#color(white)(g(h(x)))=(color(red)(-3x+2))^2+4+2(color(red)(-3x+2))#
#color(white)(g(h(x)))=9x^2-12x+4+4-6x+4#
#color(white)(g(h(x)))=9x^2-18x+12#
#rArr(g○h)(1)=(9xx1^2)-(18xx1)+12#
#color(white)(rArr(g○h)(1))=9-18+12#
#color(white)(rArr(g○h)(1))=3#