Ques. 1JEE Main 2024, 27 January (Morning Shift)
If satisfies the equation x2+x+1=0 and (1+ )7=A+B +C 2, A, B, C 0, then 5(3A-2B-C) is equal to .
Answer
5
Solution
= or 2 ⇒ 3=1, 1+ =- 2
(1+ )7=(- 2)7=- 14
=- 12 2=- 2=1+
⇒ A=1, B=1, C=0
(Adding k(1+ + 2)=0 keeps 3A-2B-C=1.)
∴ 5(3A-2B-C)=5(3-2-0)=5
Answer: 5