F(n) is defined by the equation F(n) = F(n − 1) + n for every integer

Question

F(n) is defined by the equation F(n) = F(n − 1) + n for every integer n greater than 1. If F(1) = 0, what is the value of F(3)?

A. 3
B. 4
C. 5
D. 6
E. 7

chayma · Answer

Is the right answer 5 ?

Posted from my mobile device

Bunuel · Answer

F(n)=F(n-1)+n ;

F(2)=F(1) + 2=0+2=2 ;

F(3)=F(2) + 3=2+3=5 .

Answer: C.

BrushMyQuant · Answer

Given that F(n) = F(n − 1) + n for every integer n greater than 1 and F(1) = 0 and we need to find the value of F(3)

To find F(3) we need to compare what is inside the bracket in F(3) and F(n)

=> We need to substitute n with 3 in F(n) = F(n − 1) + n to get the value of F(3)

=> F(3) = F(3 − 1) + 3 = F(2) + 3

Similarly, F(2) = F(2 − 1) + 2 = F(1) + 2 = 0 + 2 = 2 (as F(1) = 0 is Given)

=> F(3) = 2 + 3 = 5

So,  Answer will be C 
Hope it helps!

Watch the following video to learn the Basics of Functions and Custom Characters

https://www.youtube.com/watch?v=b7JoMX0gk8M

Prep Toolkit