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

If √5 cosx + √15sinx = 0, for 0° < x < 360°, find the values of x.
Take Free Practice Test On 2026 JAMB UTME, Post UTME, WAEC SSCE, GCE, NECO SSCE
  • A 30° and 150°
  • B 150° and 210°
  • C 150° and 330°
  • D 210° and 330°
Correct Answer: Option C
Explanation:
√5 cosx + √15sinx = 0;
√5 (cosx + √3sinx) = 0
cosx = -sinx√3; \(\frac{sinx}{cos}\) = \(\frac{-1}{√3}\)
tanx = \(\frac{-1}{√3}\); x = 150° or 330°

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