Please provide me the answer of this question

Dear Student,

Given:- (x+y) = 4 ---------(i)
Cubing both sides we get,
=> (x+y)³ = 4³
=> x^{​​​​​​3} + y^{​​​​​​3}​​​ + 3xy(x+y) = 64
=> x​​​​​^{​​​​​​3} + y​​​​​​^{​​​​​​3} + 3xy * 4 = 64.  [  Using equation (i) ]
=> x​​​​​^{​​​​​​3} + y​​​​​​³ + 12xy -64 = 0

Hence the value of the given equation is zero.

Regards
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