JEE MATHEMATICS MCQ: COMPLEX NUMBERS

1 Easy

1 of 1

Analyzing +4 | -1

\cos A + \cos B + \cos C = 0,

\sin A + \sin B + \sin C = 0

and

A + B + C = 180^\circ ,

then the value of

\cos 3\;A + \cos 3\;B + \cos 3\;C

View answer and explanation

Correct option: B

- 3

Option C (1/3) is correct because by substituting a = 0 and b = 1, we can solve for x and y and then find the value of 1/x - 1/y.

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