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If √5 cosx + √15sinx = 0, for 0° < x &...

If √5 cosx + √15sinx = 0, for 0° < x < 360°, find the values of x.

A.

30° and 150°

B.

150° and 210°

C.

150° and 330°

D.

210° and 330°

Correct answer is C

√5 cosx + √15sinx = 0;

√5 (cosx + √3sinx) = 0

cosx = -sinx√3;  sinxcos = 13

tanx =  13;  x = 150° or 330°