Page 69 - TUTORIAL MATEMATIKA IPA KELAS XI-2
P. 69
LINGKARAN
56. Perhatikan gambar di bawah ini.
2
2
2
2
2
2
= + → ( + ) = ( − ) + ( )
2 2
2 2 2 2 2
→ + + = − 2 + +
4 4
2
→ 3 = → 3 = → =
3
A B
C
0
57. ∠ = 45 → ∠ = 2. 45 = 90 .
90 1 1 1 1 1
2
2
2
2
Luas tembereng = . − . . = − = ( − )
360 2 4 2 4 4
58. Panjang busur = 3.2 − 2 = 5 = 5 . 5 = 25
2
2
59. 8.9 − = 3 → 72 = 4 → 18 = → = √ 18 = 3√2
2
2
3√2
Keliling = 2 = 2 . = 6√2
60. Perhatikan gambar di bawah ini.
AO = 10 – r
2
2
2
2
2
= 5 + (10 − ) → = 25 + 100 − 20 + → 20 = 125
125 25 25 2 625
2
5 r → = = ; = = . ( ) =
20 4 4 16
A O
5
LEARNING IS FUN 68
