61) \((2b^4c+x^5)^2\)

\((2b^4c+x^5)^2=(2b^4c)^2+2\cdot2b^4c\cdot x^5+(x^5)^2=4b^8c^2+4b^4cx^5+x^{10}\).

Ответ: \(4b^8c^2+4b^4cx^5+x^{10}\).