If a + b = c, then the expression a3 + b3 - c3 + 3 abc will be equal to
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 0.
a + b = c .....(1)
Now, a3 + b3 - c3 + 3 abc
= a3 + b3 - (a + b)3 + 3ab(a + b)
= a3 + b3 - (a3 + 3a2b + 3ab2 + b3) + 3ab(a + b)
= a3 + b3 - a3 - 3a2b - 3ab2 - b3 + 3a2b + 3ab2
= 0
Therefore, the required value is 0.