Sečti mnohočleny:
\large \left( 3a^{n+1} +10a^{n} - 7a\right) + \left( a - 9a^{n+1} - 10a^{n} \right)
\large =- 5{a^{n+1}} - 6a
\large =- 6{a^{n+1}} + 6a
\large =- 6{a^{n+1}} - 6a
\large =- 6{a^{n+1}} - 7a