Sort:  

It is a wrong answer

that would be 45

f(1,4)=5
f(2,5)=12
f(3,6)=21
f(5,8)=a
solve for a
=> f(a,b)=a * b+a
f(5,8)=5 * 8+5=45
answer: 45

Coin Marketplace

STEEM 0.06
TRX 0.30
JST 0.054
BTC 74028.94
ETH 2308.10
USDT 1.00
SBD 0.51