9th one pls fast as soon as possible
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Answer
Value of a3³+b³-3ab = -1
Explanation
Given a+b=-1----(1)
On cubeing both sides of equation (1), we get
(a+b)³ = (-1)³
Call 98%
we know the algebraic identity:
(x+y)³ = x³+y³ + 3xy(x+y)
=> 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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