Answer: a. 90°
Step-by-step explanation:
We know that the in a circle, the measure of an inscribed angle is half the measure of the central angle with the same intercepted arc.
In the problem∠XYZ is the inscribed angle
∠XYZ=
⇒ ∠XYZ=
Since XZ is a diameter of the circle which is a line segment, thus ∠XZ=180°
∴ ∠XYZ=
∴ ∠XYZ=
Therefore, a. 90° is the measure of ∠XYZ.
Answer:
2 -
Step-by-step explanation:
Using the addition formula for tangent
tan(A - B) = and the exact values
tan45° = 1 , tan60° = , then
tan15° = tan(60 - 45)°
tan(60 - 45)°
=
=
Rationalise the denominator by multiplying numerator/ denominator by the conjugate of the denominator.
The conjugate of 1 + is 1 -
= ← expand numerator/denominator using FOIL
=
=
= +
= 2 -
