1.
Express the following sexagesimal measure as radian measure and centesimal system
i) 45°
ii) 270°
iii) 72°
iv) 108°
Answers
Answer:
1)
45°
In centisimal system
90° = 100 grade
dividing by 2 on both sides we get
45° = 50 grades
In Radian system
we know that
180° = π radians
Dividing by 4 we get
45° = (π/4) radians
2)
270°
In centisimal system
90° = 100 grade
Multiplying by 3 on both sides we get
270° = 300 grades
In Radian system
we know that
180° = π radians
Multiplying by 3/2 both sides we get
270° = (3π/2) radians
3)
72°
In centisimal system
90° = 100 grade
Dividing by 90 on both sides we get
1° = (100/90) grades
Multiplying by 72 on both sides we get
72° = 7200/90 = 720/9 grades = 80 grades
So
72° = 80 grades
In Radian system
we know that
180° = π radians
Dividing by 180 both sides we get
1° = (π/180) radians
Multiplying by 72 on both sides we get
72° = (72π/180) radians = (8π/20) radians = (2π/5) radians
So
72° = (2π/5) radians
4)
108°
In centisimal system
90° = 100 grade
Dividing by 90 on both sides we get
1° = (100/90) grades
Multiplying by 108 on both sides we get
108° = 10800/90 = 1080/9 grades = 120 grades
So
108° = 120 grades
In Radian system
we know that
180° = π radians
Dividing by 180 both sides we get
1° = (π/180) radians
Multiplying by 108 on both sides we get
108° = (108π/180) = (6π/10) = (3π/5) radians
So
108° = (3π/5) radians
Answer:
The above answer is correct