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In a circle with centre
MATHEMATICS · Multi-part · CBSE · Mathematics · Circles · Circles
Problem
In a circle with centre
O
O
O
,
A
B
AB
A
B
is a diameter and
C
C
C
is any point on the circle other than
A
A
A
or
B
B
B
. The measure of
∠
C
A
B
\angle CAB
∠
C
A
B
is
30
∘
30^{\circ}
3
0
∘
. (i) Calculate
∠
C
B
A
\angle CBA
∠
C
B
A
. (ii) Determine
∠
C
O
B
\angle COB
∠
C
O
B
. (iii) Find
∠
A
C
B
\angle ACB
∠
A
C
B
. Give reasons for every step of your work.
Related theory
Properties of Triangles
Triangle Properties
Circles
Circle angle properties
Angle subtended by a chord
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