JEE MAIN - Mathematics (2021 - 26th February Morning Shift - No. 17)

The sum of 162th power of the roots of the equation x3 $$-$$ 2x2 + 2x $$-$$ 1 = 0 is ________.
Answer
3

Explanation

x3 $$-$$ 2x2 + 2x $$-$$ 1 = 0

x = 1 satisfying the equation

$$ \therefore $$ x $$-$$ 1 is factor of

x3 $$-$$ 2x2 + 2x $$-$$ 1

= (x $$-$$ 1) (x2 $$-$$ x + 1) = 0

x = 1, $${{1 + i\sqrt 3 } \over 2},{{1 - i\sqrt 3 } \over 2}$$

x = 1, $$-$$ $$\omega$$2, $$-$$$$\omega$$

Sum of 162th power of roots

= (1)162 + ($$-$$$$\omega$$2)162 + ($$-$$$$\omega$$)162

= 1 + ($$\omega$$)324 + ($$\omega$$)162

= 1 + 1 + 1 = 3

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