Question

ab=a^2+b^2+a+b+1, then a^3+b^3+3ab=

Answer 1

Value of a³+b³-3ab = -1

Explanation:

Given a+b=-1 ----(1)

On cubeing both sides of equation (1), we get

(a+b)³ = (-1)³

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we know the algebraic identity:

\boxed {(x+y)^{3}=x^{3}+y^{3}+3xy(x+y)}

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=> a³+b³+3ab(a+b)= -1

=> a³+b³+3ab(-1)=-1

/* from (1)*/

=> a³+b³-3ab = -1

Therefore,

Value of a³+b³-3ab = -1

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I hope it's helpful for you....