JEE Advance - Mathematics (1997 - No. 16)
The real roots of the equation $$\,{\cos ^7}x + {\sin ^4}x = 1$$ in the interval $$\left( { - \pi ,\pi } \right)$$ are ...., ...., and ______.
$${pi over 2},{pi over 4},0$$
$${pi over 2},{pi over 3},0$$
$$ - {pi over 2},{pi over 2},0$$
$$ - {pi over 2},{pi over 4},0$$
$$ - {pi over 2},{pi over 3},0$$