√4 + ∛8 + √25 =√64 - √49 + √1 =√5 + √16 =√7, 5 + 1 =∛125 + √16 - √18 =∛√25 + √9 =5√19 - ∛8 =√10 + √36 =∛27 + 4√14 - ∛32 =√8 + ∛1 =?

Tu tienes definición :

<img src="https://tex.z-dn.net/?f=%5Csqrt%7Ba%7D%3Db%20%5Cqquad%20%5CRightarrow%20%5Cqquad%20b%5E%7B2%7D%3Da%20%5Cqquad%20a%2Cb%20%5Cge%200%20%5C%5C%20%5Csqrt%5B3%5D%7Ba%7D%3Db%20%5Cqquad%20%5CRightarrow%20%5Cqquad%20b%5E%7B3%7D%3Da" />

<img src="https://tex.z-dn.net/?f=%5Csqrt%7B4%7D%2B%5Csqrt%5B3%5D%7B8%7D%2B%5Csqrt%7B25%7D%3D2%2B2%2B5%3D9%20%5C%5C%20%5Csqrt%7B64%7D-%5Csqrt%7B49%7D%2B%5Csqrt%7B1%7D%3D8-7%2B1%3D2%20%5C%5C%20%5Csqrt%7B5%7D%2B%5Csqrt%7B16%7D%3D%5Csqrt%7B5%7D%2B4%20%5C%5C%20%5Csqrt%7B7%2C5%7D%2B1%20%5C%20%5Chbox%7Bes%20no%20contar%7D%20%5C%5C%20%5Csqrt%5B3%5D%7B125%7D%2B%5Csqrt%7B16%7D-%5Csqrt%7B18%7D%3D5%2B4-%5Csqrt%7B9%20%5Ccdot%202%7D%3D9-3%5Csqrt%7B2%7D%20%5C%5C%20%5Csqrt%5B3%5D%7B%5Csqrt%7B25%7D%2B%5Csqrt%7B9%7D%7D%3D%5Csqrt%5B3%5D%7B5%2B3%7D%3D%5Csqrt%5B3%5D%7B8%7D%3D2%20%5C%5C%205%5Csqrt%7B19%7D-%5Csqrt%5B3%5D%7B8%7D%3D5%5Csqrt%7B19%7D-2%20%5C%5C%20%5Csqrt%7B10%7D%2B%5Csqrt%7B36%7D%3D%5Csqrt%7B10%7D%2B6%20%5C%5C%20%5Csqrt%5B3%5D%7B27%7D%2B4%5Csqrt%7B14%7D-%5Csqrt%5B3%5D%7B32%7D%3D3%2B4%5Csqrt%7B14%7D-%5Csqrt%5B3%5D%7B8%20%5Ccdot%204%7D%3D3%2B4%5Csqrt%7B14%7D-2%5Csqrt%5B3%5D%7B4%7D%20%5C%5C%20%5Csqrt%7B8%7D%2B%5Csqrt%5B3%5D%7B1%7D%3D%5Csqrt%7B4%20%5Ccdot%202%7D%2B1%3D2%5Csqrt%7B2%7D%2B1" />.