What is the standard form of #f(x)=(x+1)(x+3)+(x+5)^2 #?

1 Answer
Mar 8, 2016

#f(x)=color(purple)(2x^2+14x+28)#

Explanation:

#f(x)=(x+1)(x+3)+(x+5)^2#

Simplify.

#f(x)=color(red)((x+1)(x+3))+color(blue)((x+5)(x+5))#

FOIL each pair of binomials.
http://www.mesacc.edu/~scotz47781/mat120/notes/polynomials/foil_method/foil_method.html

#f(x)=color(red)((x*x+3*x+1*x+1*3))+color(blue)((x*x+5*x+5*x+5*5))#

Simplify.

#f(x)=color(red)(x^2+3x+x+3)+color(blue)(x^2+5x+5x+25)#

Gather like terms.

#f(x)=color(red)(x^2)+color(blue)(x^2)+color(red)(3x)+color(red)(x)+color(blue)(5x)+color(blue)(5x)+color(red)(3)+color(blue)(25)#

Simplify.

#f(x)=color(purple)(2x^2+14x+28)#