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Tuesday, 03 March 2026
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Find the value of \(\theta\) in the diagram



Find the value of \(\theta\) in the diagram
Take Free Practice Test On 2026 JAMB UTME, Post UTME, WAEC SSCE, GCE, NECO SSCE
  • A 60o
  • B 100o
  • C 120o
  • D 30o
Correct Answer: Option C
Explanation:
Using cosine formula (t\(\sqrt{3}\))2 = t2 + t2 - 2t2 cos\(\theta\)
3t2 = 2t2 - 2t2 cos\(\theta\) = 2t2(1 - cos\(\theta\))
1 - cos\(\theta\) = \(\frac{3t^2}{2t^2}\) = \(\frac{3}{2}\)
cos = 1 - \(\frac{3}{2} = -\frac{1}{2}\)
\(\theta\) = cos-1(-\(\frac{1}{2}\)) = 120o and 240o
N.B 0 \(\geq\) \(\theta\) 360

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