Question

If a+b=-1 then the value of a³+b³-3ab is​

Answer 1

Answer:

answer is 1

Step-by-step explanation:

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

a²-ab+ab-b²=1

a²+b²=1

(a+b)²=a²+b²+2ab

(-1)²=(1)+2ab

1-1=2ab

ab=0

(a-b)²=a²+b²-2ab

(a-b)²= 1-2(0)

a-b=√1

a-b=1

(a-b)³ =a³+b³-3ab

(1)³ =a³+b³-3(0)

a³+b³=1

value of a³+b³-3ab

1-3(0)

=1