Question 1157944

{{{ D(f)= ((f+0.5)/(f+5))*((6)/(f^3+4f^2+3f)) }}}


{{{ D(f)= ((f+0.5)6)/((f+5)(f^3+4f^2+3f)) }}}


{{{ D(f)= (6f+3)/(f^4 + 9f^3 + 23f^2 + 15f) }}}