A chord AC subtends an angle of 90° at the center O. If the radius of the circle is 8 cm, what is the length of the chord AC?
Show answer & explanation
Correct answer: A
Explanation
Given:
Radius (r) = 8 cm
∠AOC = 90°
Formula:
Length of chord = 2r sin(θ/2)
AC = 2 × 8 × sin(90°/2)
AC = 16 × sin45°
AC = 16 × (1/√2)
AC = 16/√2
AC = 8√2
Chord AC = 8√2 cm