Question

functia f:R->R, f(x)=x+3
calculati: S=f(1)+f(2)+f(3)+...+f(55)

Answer 1

F(1)=1+3
F(2)=2+3
F(3)=3+3
.
.
.
.
F(55)=55+3

F(1)+F(2)+F(3)+...+F(55)=(1+2+3+...+55)+3X55=
55x56 supra 2 + 3x55
=1540+165
=1705