Let
We define Then ar is equal to.
- $\binom{r}{2019}$
- $\binom{r}{r + 2018}$
- $\binom{r}{2019 – r}$
- $\binom{r}{r – 2018}$
Can anyone tell me if this type of question is in Gate 2019 syllabus or not because I have never seen such question in previous year question? If yes, then when can I learn this stuff from. Because I am unable to understand the whole solution.