If a = 299, b = 298, c = 297 then the value of 2a3 + 2b3 + 2c3 - 6abc is:
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3 i.e. 5364
a = 299, b = 298, c = 297
2a3 + 2b3 + 2c3 - 6abc
= 2(a3 + b3 + c3 - 3abc)
= 2[(a + b + c) × 1/2((a - b)2 + (b - c)2 + (c - a)2)]
= 2[(299 + 298 + 297) × 1/2(12 + 12 + 4)]
= 2[894 × 1/2 × 6]
= 5364