Click here for the previous basics of trigonometry.
Basics of trigonometry
Now we will study some examples of trigonometry.
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Small Friends | Normal Friends
|
Big Friends
| |
1
|
4
|
9
|
14 NA
|
2
|
3
|
8
|
13 NA
|
3
|
2
|
7
|
12 NA
|
4
|
1
|
6
|
11 NA
|
5
|
0
|
5
|
10 NA
|
6
|
-
|
4
|
9
|
7
|
-
|
3
|
8
|
8
|
-
|
2
|
7
|
9
|
-
|
1
|
6
|
Digit in the units
|
Type of friends to be used
|
1, 5 or 7
| Small Friends (05)
|
2, 4, 6 or 8
| Normal Friends (10)
|
3 or 9
| Big Friends (15)
|
Digit in the units
| Type of friends to be used
|
1, 3, or 5
| Small Friends (05)
|
2, 4, 6 or 8
| Normal Friends (10)
|
7 or 9
| Big Friends (15)
|
01
|
Take the number 06 (A)
|
06
|
02
|
Double is 12, so take 2 (B). 2<6 so 0+1=1, so write 12.
|
12
|
03
|
Normal-friend of 2 is 8 (C) so take 8. 8>2 so 1+0=1, so write 18
|
18
|
04
|
Normal-friend of 6 is 4 (D), so take 4. 4<8 so 1+1=2, so write 24
|
24
|
05
|
6 (A) is Even so take 0, 0<4 so 2+1=3 so write 30
|
30
|
06
|
Normal-friend of (D) 4 is 6, so take 6, 6>0 so 3+0=3, so write 36
|
36
|
07
|
Normal-friend of (C) 8 is 2, so take 2, 2<6 so 3+1=4, so write 42
|
42
|
08
|
Normal-friend of (B) 2 is 8, so take 8, 8>6 so 4+0=4, so write 48
|
48
|
09
|
Normal-friend of (A) 6 is 4, so take 4, 4<6 so 4+1=5, so write 54
|
54
|
10
|
Always take 0, 0 < 4, so 5+1=6, so write 60
|
60
|
01
|
Take the number 27 (A)
|
27
|
02
|
Double is 14, so take 4 (B). 4<7 so 2+3=5, so write 54.
|
54
|
03
|
Small-friend of 4 is 1 (C) so take 1. 1<4 so 5+3=8, so write 81
|
81
|
04
|
Big friend of 7 is 8 (D), so take 8. 8>1 so 8+2=10, so write 108
|
108
|
05
|
7 (A) is Odd so take 5, 5<8 so 10+3=13 so write 135
|
135
|
06
|
Normal friend of 8 (D) is 2, so take 2, 2<5 so 13+3=16, so write 162
|
162
|
07
|
Normal friend of 1 (C) is 9, so take 9, 9>2 so 16+2=18, so write 189
|
189
|
08
|
Normal-friend of 4 (B) is 6, so take 6, 6<9 so 18+3=21, so write 216
|
216
|
09
|
Normal-friend of 7 (A) is 3, so take 3, 3<6 so 21+3=24, so write 243
|
243
|
10
|
Always take 0, 0<3, so 24+3=27, so write 270
|
270
|