# GATE2018-19

Which one of the following is the solution for $\cos^2 x + 2 \cos x + 1 = 0$, for values of $x$ in the range of $0^\circ < x < 360^\circ$

1. $45^\circ$
2. $90^\circ$
3. $180^\circ$
4. $270^\circ$
in Calculus
recategorized

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