Question

If x = 2, y = 8, find (i) x³+y³ (ii) ∛y

Answer 1

( i ) 520

( ii ) 2

Explanation:

We can find this solution by plugging in known values -

If x = 2, y = 8

x³+y³ = ( 2 )³ + ( 8 )³ = 8 + 512

= 520

Know let us move on to the second half -

We only need one part of this information now, y = 8. If so,

∛y = ∛8

2 x 2 x 2 = 8 - and thus 2 should be our solution for this portion.

Answer 2

(i) 520

(ii) 2

Explanation:

(i) x³ + y³

Plug x as 2, and y as 8.

(2)³ + (8)³

Solve for exponents.

8 + 512

Add.

= 520

(ii) ∛y

Plug y as 8.

∛(8)

Solve for cube root.

= 2