Q8 · 2025 · Technology-activeSimple familiar1 mark
QUESTION 8
Consider the plane that contains both the -axis and the -axis. A sphere centred at touches this plane.
The length of the radius of the sphere is
(A)
units.
(B)
units.
(C)
units.
(D)
units.
WORKED SOLUTION
1 markAnswer D
ANSWER
D — units
Worked solution
The plane containing the - and -axes is . A sphere touching the plane has radius equal to the perpendicular distance from its centre to the plane, which is units.
Selects option D.
Worked explanation by QCE Vault; correct option verified against the QCAA answer key.
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