Question

यद‌ि `a^(2)+a+1=0` है तो `a^(9)` का मान क्‍या है?
A. 2
B. 3
C. 1
D. 0

Answer 1

Correct Answer - C
`a^(2)+a+1=0`
`[(a^(3)+1^(3)=(a+1)(a^(2)-a+1))/(a^(3)-1=(a-1)(a^(2)+1+a))]`
`:. (a^(3)-1)=(a-1)xx0`
`a^(3)-1=0`
`a^(3)=1`
`(a^(3))^(3)=1^(3)`
`a^(9)=1`