Question

when we multiplied a binomial to a trinomial we get a result with only 4 terms.why?

Answer 1

$$\begin{gathered} \mathrm{Dear}\mathrm{Student}, \\ \mathrm{In}\mathrm{the}\mathrm{process}\mathrm{of}\mathrm{multiplying},\mathrm{two}\mathrm{terms}\mathrm{containg}\mathrm{term}\mathrm{x}\mathrm{will}\mathrm{gets}\mathrm{added}/\mathrm{subtracted} \\ \mathrm{so}\mathrm{forming}\mathrm{one}\mathrm{term}.\mathrm{That}\mathrm{is}\mathrm{the}\mathrm{reason}. \\ \mathrm{Regards} \end{gathered}$$