Radical math problems ?

Question

I dont get these can u plz do them step by step:

1. cube root of (y^2 - 1)

2. ( 1 + x^4/3 ) x ( 1 - x^2/3 )

Answer 1

1.

This cannot be simplified beyond factorising the y^2 - 1, to give:

cube root[ (y - 1)(y + 1) ].

2.

Multiplying the 1st term from each bracket gives 1.

Multiplying the two inner terms x^(4 / 3) and 1 gives x^(4 / 3).

Multiplying the two outer terms 1 and - x^(2 / 3) gives - x^(2 / 3).

Multiplying the last term from each bracket gives:

- x^(4 / 3 + 2 / 3)

= - x^[ (4 + 2) / 3 ]

= - x^2.

Adding all four results gives:

1 + x^(4 / 3) - x^(2 / 3) - x^2.