JAMB - Mathematics (2024 - No. 9)
From the figure above, find the length of Chord PQ
17cm
18cm
7cm
9cm
คำอธิบาย
Length of a chord = 2rSin\(\frac{\theta}{2}\)
\(\theta\) = 60º not 30º and radius = 9cm
Therefore, Length of the chord = 2 x 9 Sin\(\frac{60º}{2}\) = 2 x 9 x Sin 30º = 2 x 9 x \(\frac{1}{2}\) = 9cm.